diff --git a/src/3d/chunks/qgschunkedentity_p.cpp b/src/3d/chunks/qgschunkedentity_p.cpp
index e12067df7462..bdd7a273d9b4 100644
--- a/src/3d/chunks/qgschunkedentity_p.cpp
+++ b/src/3d/chunks/qgschunkedentity_p.cpp
@@ -131,7 +131,7 @@ void QgsChunkedEntity::update( const SceneState &state )
 
   int oldJobsCount = pendingJobsCount();
 
-  QSet<QgsChunkNode *> activeBefore = QSet<QgsChunkNode *>::fromList( mActiveNodes );
+  QSet<QgsChunkNode *> activeBefore = qgis::listToSet( mActiveNodes );
   mActiveNodes.clear();
   mFrustumCulled = 0;
   mCurrentTime = QTime::currentTime();
diff --git a/src/3d/qgs3dmapscene.cpp b/src/3d/qgs3dmapscene.cpp
index cf3041896db2..dc09be0a487a 100644
--- a/src/3d/qgs3dmapscene.cpp
+++ b/src/3d/qgs3dmapscene.cpp
@@ -516,7 +516,7 @@ void Qgs3DMapScene::onLayerRenderer3DChanged()
 
 void Qgs3DMapScene::onLayersChanged()
 {
-  QSet<QgsMapLayer *> layersBefore = QSet<QgsMapLayer *>::fromList( mLayerEntities.keys() );
+  QSet<QgsMapLayer *> layersBefore = qgis::listToSet( mLayerEntities.keys() );
   QList<QgsMapLayer *> layersAdded;
   Q_FOREACH ( QgsMapLayer *layer, mMap.layers() )
   {
diff --git a/src/analysis/network/qgsvectorlayerdirector.cpp b/src/analysis/network/qgsvectorlayerdirector.cpp
index d020adde8fb9..13b3883fc660 100644
--- a/src/analysis/network/qgsvectorlayerdirector.cpp
+++ b/src/analysis/network/qgsvectorlayerdirector.cpp
@@ -85,7 +85,7 @@ QgsAttributeList QgsVectorLayerDirector::requiredAttributes() const
   {
     attrs.unite( strategy->requiredAttributes() );
   }
-  return attrs.toList();
+  return qgis::setToList( attrs );
 }
 
 QgsVectorLayerDirector::Direction QgsVectorLayerDirector::directionForFeature( const QgsFeature &feature ) const
diff --git a/src/analysis/processing/qgsalgorithmcategorizeusingstyle.cpp b/src/analysis/processing/qgsalgorithmcategorizeusingstyle.cpp
index 83f987106d1d..96879699e004 100644
--- a/src/analysis/processing/qgsalgorithmcategorizeusingstyle.cpp
+++ b/src/analysis/processing/qgsalgorithmcategorizeusingstyle.cpp
@@ -204,7 +204,7 @@ QVariantMap QgsCategorizeUsingStyleAlgorithm::processAlgorithm( const QVariantMa
     uniqueVals << value;
   }
 
-  QVariantList sortedUniqueVals = uniqueVals.toList();
+  QVariantList sortedUniqueVals = qgis::setToList( uniqueVals );
   std::sort( sortedUniqueVals.begin(), sortedUniqueVals.end() );
 
   QgsCategoryList cats;
diff --git a/src/analysis/processing/qgsalgorithmdeleteduplicategeometries.cpp b/src/analysis/processing/qgsalgorithmdeleteduplicategeometries.cpp
index 20f8e25b832a..d0c22258afed 100644
--- a/src/analysis/processing/qgsalgorithmdeleteduplicategeometries.cpp
+++ b/src/analysis/processing/qgsalgorithmdeleteduplicategeometries.cpp
@@ -164,7 +164,7 @@ QVariantMap QgsDeleteDuplicateGeometriesAlgorithm::processAlgorithm( const QVari
 
   // now, fetch all the feature attributes for the unique features only
   // be super-smart and don't re-fetch geometries
-  QSet< QgsFeatureId > outputFeatureIds = uniqueFeatures.keys().toSet();
+  QSet< QgsFeatureId > outputFeatureIds = qgis::listToSet( uniqueFeatures.keys() );
   outputFeatureIds.unite( nullGeometryFeatures );
   step = outputFeatureIds.empty() ? 1 : 100.0 / outputFeatureIds.size();
 
diff --git a/src/analysis/processing/qgsalgorithmlineintersection.cpp b/src/analysis/processing/qgsalgorithmlineintersection.cpp
index 3380cb403663..9f6fd8287fcf 100644
--- a/src/analysis/processing/qgsalgorithmlineintersection.cpp
+++ b/src/analysis/processing/qgsalgorithmlineintersection.cpp
@@ -125,7 +125,7 @@ QVariantMap QgsLineIntersectionAlgorithm::processAlgorithm( const QVariantMap &p
       continue;
 
     QgsGeometry inGeom = inFeatureA.geometry();
-    QgsFeatureIds lines = spatialIndex.intersects( inGeom.boundingBox() ).toSet();
+    QgsFeatureIds lines = qgis::listToSet( spatialIndex.intersects( inGeom.boundingBox() ) );
     if ( !lines.empty() )
     {
       // use prepared geometries for faster intersection tests
diff --git a/src/analysis/processing/qgsalgorithmrandomextract.cpp b/src/analysis/processing/qgsalgorithmrandomextract.cpp
index 9be79992481c..23825a306285 100644
--- a/src/analysis/processing/qgsalgorithmrandomextract.cpp
+++ b/src/analysis/processing/qgsalgorithmrandomextract.cpp
@@ -121,7 +121,7 @@ QVariantMap QgsRandomExtractAlgorithm::processAlgorithm( const QVariantMap &para
     idsCount[ id ] += 1;
   }
 
-  QgsFeatureIds ids = QSet< QgsFeatureId >::fromList( idsCount.keys() );
+  QgsFeatureIds ids = qgis::listToSet( idsCount.keys() );
   QgsFeatureIterator fit = source->getFeatures( QgsFeatureRequest().setFilterFids( ids ), QgsProcessingFeatureSource::FlagSkipGeometryValidityChecks );
 
   QgsFeature f;
diff --git a/src/analysis/processing/qgsalgorithmserviceareafromlayer.cpp b/src/analysis/processing/qgsalgorithmserviceareafromlayer.cpp
index a06b8ba410ad..b36507a681c3 100644
--- a/src/analysis/processing/qgsalgorithmserviceareafromlayer.cpp
+++ b/src/analysis/processing/qgsalgorithmserviceareafromlayer.cpp
@@ -199,7 +199,7 @@ QVariantMap QgsServiceAreaFromLayerAlgorithm::processAlgorithm( const QVariantMa
     } // costs
 
     // convert to list and sort to maintain same order of points between algorithm runs
-    QList< int > verticesList = vertices.toList();
+    QList< int > verticesList = qgis::setToList( vertices );
     areaPoints.reserve( verticesList.size() );
     std::sort( verticesList.begin(), verticesList.end() );
     for ( int v : verticesList )
diff --git a/src/analysis/processing/qgsalgorithmserviceareafrompoint.cpp b/src/analysis/processing/qgsalgorithmserviceareafrompoint.cpp
index 4d40a7595d50..2431727e9342 100644
--- a/src/analysis/processing/qgsalgorithmserviceareafrompoint.cpp
+++ b/src/analysis/processing/qgsalgorithmserviceareafrompoint.cpp
@@ -164,7 +164,7 @@ QVariantMap QgsServiceAreaFromPointAlgorithm::processAlgorithm( const QVariantMa
   } // costs
 
   // convert to list and sort to maintain same order of points between algorithm runs
-  QList< int > verticesList = vertices.toList();
+  QList< int > verticesList = qgis::setToList( vertices );
   points.reserve( verticesList.size() );
   std::sort( verticesList.begin(), verticesList.end() );
   for ( int v : verticesList )
diff --git a/src/analysis/processing/qgsalgorithmsplitwithlines.cpp b/src/analysis/processing/qgsalgorithmsplitwithlines.cpp
index d7047ae22f47..fa9abdc77c41 100644
--- a/src/analysis/processing/qgsalgorithmsplitwithlines.cpp
+++ b/src/analysis/processing/qgsalgorithmsplitwithlines.cpp
@@ -146,7 +146,7 @@ QVariantMap QgsSplitWithLinesAlgorithm::processAlgorithm( const QVariantMap &par
 
     QVector< QgsGeometry > inGeoms = inGeom.asGeometryCollection();
 
-    const QgsFeatureIds lines = spatialIndex.intersects( inGeom.boundingBox() ).toSet();
+    const QgsFeatureIds lines = qgis::listToSet( spatialIndex.intersects( inGeom.boundingBox() ) );
     if ( !lines.empty() ) // has intersection of bounding boxes
     {
       QVector< QgsGeometry > splittingLines;
diff --git a/src/analysis/processing/qgsoverlayutils.cpp b/src/analysis/processing/qgsoverlayutils.cpp
index 46d6cdb69cd8..4a9667368f3a 100644
--- a/src/analysis/processing/qgsoverlayutils.cpp
+++ b/src/analysis/processing/qgsoverlayutils.cpp
@@ -104,7 +104,7 @@ void QgsOverlayUtils::difference( const QgsFeatureSource &sourceA, const QgsFeat
     if ( featA.hasGeometry() )
     {
       QgsGeometry geom( featA.geometry() );
-      QgsFeatureIds intersects = indexB.intersects( geom.boundingBox() ).toSet();
+      QgsFeatureIds intersects = qgis::listToSet( indexB.intersects( geom.boundingBox() ) );
 
       QgsFeatureRequest request;
       request.setFilterFids( intersects );
@@ -209,7 +209,7 @@ void QgsOverlayUtils::intersection( const QgsFeatureSource &sourceA, const QgsFe
       continue;
 
     QgsGeometry geom( featA.geometry() );
-    QgsFeatureIds intersects = indexB.intersects( geom.boundingBox() ).toSet();
+    QgsFeatureIds intersects = qgis::listToSet( indexB.intersects( geom.boundingBox() ) );
 
     QgsFeatureRequest request;
     request.setFilterFids( intersects );
diff --git a/src/analysis/vector/geometry_checker/qgsfeaturepool.cpp b/src/analysis/vector/geometry_checker/qgsfeaturepool.cpp
index 2ed81964f1da..63ad27929049 100644
--- a/src/analysis/vector/geometry_checker/qgsfeaturepool.cpp
+++ b/src/analysis/vector/geometry_checker/qgsfeaturepool.cpp
@@ -100,7 +100,7 @@ QgsFeatureIds QgsFeaturePool::allFeatureIds() const
 QgsFeatureIds QgsFeaturePool::getIntersects( const QgsRectangle &rect ) const
 {
   QgsReadWriteLocker locker( mCacheLock, QgsReadWriteLocker::Read );
-  QgsFeatureIds ids = QgsFeatureIds::fromList( mIndex.intersects( rect ) );
+  QgsFeatureIds ids = qgis::listToSet( mIndex.intersects( rect ) );
   return ids;
 }
 
diff --git a/src/analysis/vector/geometry_checker/qgsgeometryfollowboundariescheck.cpp b/src/analysis/vector/geometry_checker/qgsgeometryfollowboundariescheck.cpp
index c17e9d1923d8..95dfd2e8b140 100644
--- a/src/analysis/vector/geometry_checker/qgsgeometryfollowboundariescheck.cpp
+++ b/src/analysis/vector/geometry_checker/qgsgeometryfollowboundariescheck.cpp
@@ -62,7 +62,7 @@ void QgsGeometryFollowBoundariesCheck::collectErrors( const QMap<QString, QgsFea
     // Get potential reference features
     QgsRectangle searchBounds = geomt.constGet()->boundingBox();
     searchBounds.grow( mContext->tolerance );
-    QgsFeatureIds refFeatureIds = mIndex->intersects( searchBounds ).toSet();
+    QgsFeatureIds refFeatureIds = qgis::listToSet( mIndex->intersects( searchBounds ) );
 
     QgsFeatureRequest refFeatureRequest = QgsFeatureRequest().setFilterFids( refFeatureIds ).setNoAttributes();
     QgsFeatureIterator refFeatureIt = mCheckLayer->getFeatures( refFeatureRequest );
diff --git a/src/analysis/vector/qgsgeometrysnapper.cpp b/src/analysis/vector/qgsgeometrysnapper.cpp
index 66a768ccb17c..60c90216b747 100644
--- a/src/analysis/vector/qgsgeometrysnapper.cpp
+++ b/src/analysis/vector/qgsgeometrysnapper.cpp
@@ -485,7 +485,7 @@ QgsGeometry QgsGeometrySnapper::snapGeometry( const QgsGeometry &geometry, doubl
   mIndexMutex.lock();
   QgsRectangle searchBounds = geometry.boundingBox();
   searchBounds.grow( snapTolerance );
-  QgsFeatureIds refFeatureIds = mIndex.intersects( searchBounds ).toSet();
+  QgsFeatureIds refFeatureIds = qgis::listToSet( mIndex.intersects( searchBounds ) );
   mIndexMutex.unlock();
 
   QgsFeatureRequest refFeatureRequest = QgsFeatureRequest().setFilterFids( refFeatureIds ).setNoAttributes();
@@ -758,7 +758,7 @@ QgsGeometry QgsInternalGeometrySnapper::snapFeature( const QgsFeature &feature )
     // Get potential reference features and construct snap index
     QgsRectangle searchBounds = geometry.boundingBox();
     searchBounds.grow( mSnapTolerance );
-    QgsFeatureIds refFeatureIds = mProcessedIndex.intersects( searchBounds ).toSet();
+    QgsFeatureIds refFeatureIds = qgis::listToSet( mProcessedIndex.intersects( searchBounds ) );
     if ( !refFeatureIds.isEmpty() )
     {
       QList< QgsGeometry > refGeometries;
diff --git a/src/app/dwg/qgsdwgimporter.cpp b/src/app/dwg/qgsdwgimporter.cpp
index 28345ed8e65f..1b8a1c35ad2c 100644
--- a/src/app/dwg/qgsdwgimporter.cpp
+++ b/src/app/dwg/qgsdwgimporter.cpp
@@ -834,7 +834,11 @@ void QgsDwgImporter::addLType( const DRW_LType &data )
   setString( dfn, f.get(), QStringLiteral( "name" ), name );
   SETSTRINGPTR( desc );
 
+#if QT_VERSION < QT_VERSION_CHECK(5, 14, 0)
   QVector<double> path( QVector<double>::fromStdVector( data.path ) );
+#else
+  QVector<double> path( data.path.begin(), data.path.end() );
+#endif
   OGR_F_SetFieldDoubleList( f.get(), OGR_FD_GetFieldIndex( dfn, "path" ), path.size(), path.data() );
 
   QVector<double> upath;
diff --git a/src/app/locator/qgsinbuiltlocatorfilters.cpp b/src/app/locator/qgsinbuiltlocatorfilters.cpp
index f4de8668ef50..d007c06b2a7c 100644
--- a/src/app/locator/qgsinbuiltlocatorfilters.cpp
+++ b/src/app/locator/qgsinbuiltlocatorfilters.cpp
@@ -379,7 +379,7 @@ void QgsAllLayersFeaturesLocatorFilter::prepare( const QString &string, const Qg
     expression.prepare( &context );
 
     QgsFeatureRequest req;
-    req.setSubsetOfAttributes( expression.referencedAttributeIndexes( layer->fields() ).toList() );
+    req.setSubsetOfAttributes( qgis::setToList( expression.referencedAttributeIndexes( layer->fields() ) ) );
     if ( !expression.needsGeometry() )
       req.setFlags( QgsFeatureRequest::NoGeometry );
     QString enhancedSearch = string;
diff --git a/src/app/qgisapp.cpp b/src/app/qgisapp.cpp
index 372be2c54028..eee98c67f216 100644
--- a/src/app/qgisapp.cpp
+++ b/src/app/qgisapp.cpp
@@ -12889,7 +12889,7 @@ bool QgisApp::checkTasksDependOnProject()
   if ( !activeTaskDescriptions.isEmpty() )
   {
     QMessageBox::warning( this, tr( "Active Tasks" ),
-                          tr( "The following tasks are currently running which depend on layers in this project:\n\n%1\n\nPlease cancel these tasks and retry." ).arg( activeTaskDescriptions.toList().join( QStringLiteral( "\n" ) ) ) );
+                          tr( "The following tasks are currently running which depend on layers in this project:\n\n%1\n\nPlease cancel these tasks and retry." ).arg( qgis::setToList( activeTaskDescriptions ).join( QStringLiteral( "\n" ) ) ) );
     return true;
   }
   return false;
diff --git a/src/app/qgsattributetabledialog.cpp b/src/app/qgsattributetabledialog.cpp
index d4423e3f7f31..8ba731a4933a 100644
--- a/src/app/qgsattributetabledialog.cpp
+++ b/src/app/qgsattributetabledialog.cpp
@@ -636,7 +636,7 @@ void QgsAttributeTableDialog::mActionCopySelectedRows_triggered()
     }
     featureStore.setFields( fields );
 
-    QgsFeatureIterator it = mLayer->getFeatures( QgsFeatureRequest( featureIds.toSet() )
+    QgsFeatureIterator it = mLayer->getFeatures( QgsFeatureRequest( qgis::listToSet( featureIds ) )
                             .setSubsetOfAttributes( fieldNames, mLayer->fields() ) );
     QgsFeatureMap featureMap;
     QgsFeature feature;
diff --git a/src/app/qgsbookmarkeditordialog.cpp b/src/app/qgsbookmarkeditordialog.cpp
index c957b663ab58..d06522e736ea 100644
--- a/src/app/qgsbookmarkeditordialog.cpp
+++ b/src/app/qgsbookmarkeditordialog.cpp
@@ -39,8 +39,8 @@ QgsBookmarkEditorDialog::QgsBookmarkEditorDialog( QgsBookmark bookmark, bool inP
 
   mName->setText( mBookmark.name() );
 
-  QSet<QString> groups = QSet<QString>::fromList( QgsProject::instance()->bookmarkManager()->groups() << QgsApplication::instance()->bookmarkManager()->groups() );
-  QStringList groupsList = groups.toList();
+  QSet<QString> groups = qgis::listToSet( QgsProject::instance()->bookmarkManager()->groups() << QgsApplication::instance()->bookmarkManager()->groups() );
+  QStringList groupsList = qgis::setToList( groups );
   groupsList.removeOne( QString() );
   groupsList.sort();
   mGroup->addItems( groupsList );
diff --git a/src/app/qgsdxfexportdialog.cpp b/src/app/qgsdxfexportdialog.cpp
index 1c54816ed977..0ff5aa45fcd1 100644
--- a/src/app/qgsdxfexportdialog.cpp
+++ b/src/app/qgsdxfexportdialog.cpp
@@ -350,7 +350,7 @@ void QgsVectorLayerAndAttributeModel::applyVisibilityPreset( const QString &name
   }
   else
   {
-    visibleLayers = QgsProject::instance()->mapThemeCollection()->mapThemeVisibleLayerIds( name ).toSet();
+    visibleLayers = qgis::listToSet( QgsProject::instance()->mapThemeCollection()->mapThemeVisibleLayerIds( name ) );
   }
 
   if ( visibleLayers.isEmpty() )
diff --git a/src/app/qgsgeometryvalidationmodel.cpp b/src/app/qgsgeometryvalidationmodel.cpp
index 45a8a543a0b7..47505ff337f0 100644
--- a/src/app/qgsgeometryvalidationmodel.cpp
+++ b/src/app/qgsgeometryvalidationmodel.cpp
@@ -246,7 +246,7 @@ void QgsGeometryValidationModel::setCurrentLayer( QgsVectorLayer *currentLayer )
     mDisplayExpression = mCurrentLayer ? mCurrentLayer->displayExpression() : QString();
     mExpressionContext = QgsExpressionContext( QgsExpressionContextUtils::globalProjectLayerScopes( mCurrentLayer ) );
     mDisplayExpression.prepare( &mExpressionContext );
-    mRequiredAttributes = mDisplayExpression.referencedColumns().toList();
+    mRequiredAttributes = qgis::setToList( mDisplayExpression.referencedColumns() );
   }
   else
   {
diff --git a/src/app/qgsgeometryvalidationservice.cpp b/src/app/qgsgeometryvalidationservice.cpp
index 2eb2764938ca..5c9546132b55 100644
--- a/src/app/qgsgeometryvalidationservice.cpp
+++ b/src/app/qgsgeometryvalidationservice.cpp
@@ -414,8 +414,8 @@ void QgsGeometryValidationService::triggerTopologyChecks( QgsVectorLayer *layer
   QgsFeatureIds affectedFeatureIds;
   if ( layer->editBuffer() )
   {
-    affectedFeatureIds = layer->editBuffer()->changedGeometries().keys().toSet();
-    affectedFeatureIds.unite( layer->editBuffer()->addedFeatures().keys().toSet() );
+    affectedFeatureIds = qgis::listToSet( layer->editBuffer()->changedGeometries().keys() );
+    affectedFeatureIds.unite( qgis::listToSet( layer->editBuffer()->addedFeatures().keys() ) );
   }
 
   const QString layerId = layer->id();
diff --git a/src/app/qgsidentifyresultsdialog.cpp b/src/app/qgsidentifyresultsdialog.cpp
index 34b0d5f946ee..44a58e0b9527 100644
--- a/src/app/qgsidentifyresultsdialog.cpp
+++ b/src/app/qgsidentifyresultsdialog.cpp
@@ -601,7 +601,7 @@ void QgsIdentifyResultsDialog::addFeature( QgsVectorLayer *vlayer, const QgsFeat
       QTreeWidgetItem *twi = new QTreeWidgetItem( QStringList() << QString() << action->text() );
       twi->setIcon( 0, QgsApplication::getThemeIcon( QStringLiteral( "/mAction.svg" ) ) );
       twi->setData( 0, Qt::UserRole, "map_layer_action" );
-      twi->setData( 0, Qt::UserRole + 1, qVariantFromValue( qobject_cast<QObject *>( action ) ) );
+      twi->setData( 0, Qt::UserRole + 1, QVariant::fromValue( qobject_cast<QObject *>( action ) ) );
       actionItem->addChild( twi );
 
       connect( action, &QObject::destroyed, this, &QgsIdentifyResultsDialog::mapLayerActionDestroyed );
@@ -851,7 +851,7 @@ void QgsIdentifyResultsDialog::addFeature( QgsRasterLayer *layer,
       if ( !( QgsRasterDataProvider::identifyFormatToCapability( f ) & capabilities ) )
         continue;
       formatCombo->addItem( QgsRasterDataProvider::identifyFormatLabel( f ), f );
-      formatCombo->setItemData( formatCombo->count() - 1, qVariantFromValue( qobject_cast<QObject *>( layer ) ), Qt::UserRole + 1 );
+      formatCombo->setItemData( formatCombo->count() - 1, QVariant::fromValue( qobject_cast<QObject *>( layer ) ), Qt::UserRole + 1 );
       if ( currentFormat == f )
         formatCombo->setCurrentIndex( formatCombo->count() - 1 );
     }
diff --git a/src/app/qgsmaptoolrotatepointsymbols.cpp b/src/app/qgsmaptoolrotatepointsymbols.cpp
index eb35db0eb20c..ecdd0f2c08c6 100644
--- a/src/app/qgsmaptoolrotatepointsymbols.cpp
+++ b/src/app/qgsmaptoolrotatepointsymbols.cpp
@@ -77,7 +77,7 @@ void QgsMapToolRotatePointSymbols::canvasPressEvent( QgsMapMouseEvent *e )
 void QgsMapToolRotatePointSymbols::canvasPressOnFeature( QgsMapMouseEvent *e, const QgsFeature &feature, const QgsPointXY &snappedPoint )
 {
   //find out initial arrow direction
-  QVariant attrVal = feature.attribute( mCurrentRotationAttributes.toList().at( 0 ) );
+  QVariant attrVal = feature.attribute( qgis::setToList( mCurrentRotationAttributes ).at( 0 ) );
 
   mCurrentRotationFeature = attrVal.toDouble();
   createPixmapItem( mMarkerSymbol.get() );
diff --git a/src/app/vertextool/qgsvertextool.cpp b/src/app/vertextool/qgsvertextool.cpp
index 4f496134533f..0a9e530f795f 100644
--- a/src/app/vertextool/qgsvertextool.cpp
+++ b/src/app/vertextool/qgsvertextool.cpp
@@ -1005,7 +1005,7 @@ void QgsVertexTool::tryToSelectFeature( QgsMapMouseEvent *e )
         mLockedFeatureAlternatives->alternatives.append( firstChoice );
         alternatives.remove( firstChoice );
       }
-      mLockedFeatureAlternatives->alternatives.append( alternatives.toList() );
+      mLockedFeatureAlternatives->alternatives.append( qgis::setToList( alternatives ) );
 
       if ( mLockedFeature )
       {
@@ -2222,13 +2222,13 @@ void QgsVertexTool::deleteVertex()
   QSet<Vertex> toDelete;
   if ( !mSelectedVertices.isEmpty() )
   {
-    toDelete = QSet<Vertex>::fromList( mSelectedVertices );
+    toDelete = qgis::listToSet( mSelectedVertices );
   }
   else
   {
     bool addingVertex = mDraggingVertexType == AddingVertex || mDraggingVertexType == AddingEndpoint;
     toDelete << *mDraggingVertex;
-    toDelete += QSet<Vertex>::fromList( mDraggingExtraVertices );
+    toDelete += qgis::listToSet( mDraggingExtraVertices );
 
     if ( addingVertex )
     {
diff --git a/src/core/auth/qgsauthmanager.cpp b/src/core/auth/qgsauthmanager.cpp
index 6bca38a1c510..5c7be41f0613 100644
--- a/src/core/auth/qgsauthmanager.cpp
+++ b/src/core/auth/qgsauthmanager.cpp
@@ -2266,7 +2266,7 @@ bool QgsAuthManager::updateIgnoredSslErrorsCacheFromConfig( const QgsAuthConfigS
   QList<QSslError::SslError> errenums( config.sslIgnoredErrorEnums() );
   if ( !errenums.isEmpty() )
   {
-    mIgnoredSslErrorsCache.insert( shahostport, QSet<QSslError::SslError>::fromList( errenums ) );
+    mIgnoredSslErrorsCache.insert( shahostport, qgis::listToSet( errenums ) );
     QgsDebugMsg( QStringLiteral( "Update of ignored SSL errors cache SUCCEEDED for sha:host:port = %1" ).arg( shahostport ) );
     dumpIgnoredSslErrorsCache_();
     return true;
@@ -2347,7 +2347,7 @@ bool QgsAuthManager::rebuildIgnoredSslErrorCache()
       QList<QSslError::SslError> errenums( config.sslIgnoredErrorEnums() );
       if ( !errenums.isEmpty() )
       {
-        nextcache.insert( shahostport, QSet<QSslError::SslError>::fromList( errenums ) );
+        nextcache.insert( shahostport, qgis::listToSet( errenums ) );
       }
       if ( prevcache.contains( shahostport ) )
       {
diff --git a/src/core/expression/qgsexpression.cpp b/src/core/expression/qgsexpression.cpp
index 0aba59c6e7ff..5f99fb3879dc 100644
--- a/src/core/expression/qgsexpression.cpp
+++ b/src/core/expression/qgsexpression.cpp
@@ -250,7 +250,7 @@ QSet<int> QgsExpression::referencedAttributeIndexes( const QgsFields &fields ) c
   {
     if ( fieldName == QgsFeatureRequest::ALL_ATTRIBUTES )
     {
-      referencedIndexes = fields.allAttributesList().toSet();
+      referencedIndexes = qgis::listToSet( fields.allAttributesList() );
       break;
     }
     const int idx = fields.lookupField( fieldName );
diff --git a/src/core/fieldformatter/qgsrelationreferencefieldformatter.cpp b/src/core/fieldformatter/qgsrelationreferencefieldformatter.cpp
index bb74f79778ee..c6e03b56cbac 100644
--- a/src/core/fieldformatter/qgsrelationreferencefieldformatter.cpp
+++ b/src/core/fieldformatter/qgsrelationreferencefieldformatter.cpp
@@ -147,7 +147,7 @@ QVariant QgsRelationReferenceFieldFormatter::createCache( QgsVectorLayer *layer,
 
   QgsFeatureRequest request;
   request.setFlags( QgsFeatureRequest::NoGeometry );
-  QgsAttributeList requiredAttributes = expr.referencedAttributeIndexes( referencedLayer->fields() ).toList();
+  QgsAttributeList requiredAttributes = qgis::setToList( expr.referencedAttributeIndexes( referencedLayer->fields() ) );
   requiredAttributes << referencedFieldIdx;
   request.setSubsetOfAttributes( requiredAttributes );
   QgsFeature feature;
@@ -196,7 +196,7 @@ QVariantList QgsRelationReferenceFieldFormatter::availableValues( const QVariant
     if ( referencedLayer )
     {
       int fieldIndex =  context.project()->relationManager()->relation( config[QStringLiteral( "Relation" )].toString() ).referencedFields().first();
-      values = referencedLayer->uniqueValues( fieldIndex, countLimit ).toList();
+      values = qgis::setToList( referencedLayer->uniqueValues( fieldIndex, countLimit ) );
     }
   }
   return values;
diff --git a/src/core/fieldformatter/qgsvaluerelationfieldformatter.cpp b/src/core/fieldformatter/qgsvaluerelationfieldformatter.cpp
index 8e0a601fbde9..d348780c22e9 100644
--- a/src/core/fieldformatter/qgsvaluerelationfieldformatter.cpp
+++ b/src/core/fieldformatter/qgsvaluerelationfieldformatter.cpp
@@ -147,7 +147,7 @@ QgsValueRelationFieldFormatter::ValueRelationCache QgsValueRelationFieldFormatte
   QgsExpressionContext context( QgsExpressionContextUtils::globalProjectLayerScopes( layer ) );
   descriptionExpression.prepare( &context );
   subsetOfAttributes += descriptionExpression.referencedAttributeIndexes( layer->fields() );
-  request.setSubsetOfAttributes( subsetOfAttributes.toList() );
+  request.setSubsetOfAttributes( qgis::setToList( subsetOfAttributes ) );
 
   const QString filterExpression = config.value( QStringLiteral( "FilterExpression" ) ).toString();
 
@@ -219,7 +219,7 @@ QVariantList QgsValueRelationFieldFormatter::availableValues( const QVariantMap
     if ( referencedLayer )
     {
       int fieldIndex = referencedLayer->fields().indexOf( config.value( QStringLiteral( "Key" ) ).toString() );
-      values = referencedLayer->uniqueValues( fieldIndex, countLimit ).toList();
+      values = qgis::setToList( referencedLayer->uniqueValues( fieldIndex, countLimit ) );
     }
   }
   return values;
@@ -291,7 +291,7 @@ QStringList QgsValueRelationFieldFormatter::valueToStringList( const QVariant &v
 QSet<QString> QgsValueRelationFieldFormatter::expressionFormVariables( const QString &expression )
 {
   std::unique_ptr< QgsExpressionContextScope > scope( QgsExpressionContextUtils::formScope() );
-  QSet< QString > formVariables = scope->variableNames().toSet();
+  QSet< QString > formVariables = qgis::listToSet( scope->variableNames() );
   const QSet< QString > usedVariables = QgsExpression( expression ).referencedVariables();
   formVariables.intersect( usedVariables );
   return formVariables;
@@ -300,7 +300,7 @@ QSet<QString> QgsValueRelationFieldFormatter::expressionFormVariables( const QSt
 QSet<QString> QgsValueRelationFieldFormatter::expressionParentFormVariables( const QString &expression )
 {
   std::unique_ptr< QgsExpressionContextScope > scope( QgsExpressionContextUtils::parentFormScope() );
-  QSet< QString > formVariables = scope->variableNames().toSet();
+  QSet< QString > formVariables = qgis::listToSet( scope->variableNames() );
   const QSet< QString > usedVariables = QgsExpression( expression ).referencedVariables();
   formVariables.intersect( usedVariables );
   return formVariables;
@@ -322,8 +322,7 @@ QSet<QString> QgsValueRelationFieldFormatter::expressionParentFormAttributes( co
   QgsExpression exp( expression );
   std::unique_ptr< QgsExpressionContextScope > scope( QgsExpressionContextUtils::parentFormScope() );
   // List of form function names used in the expression
-  const QSet<QString> formFunctions( scope->functionNames()
-                                     .toSet()
+  const QSet<QString> formFunctions( qgis::listToSet( scope->functionNames() )
                                      .intersect( exp.referencedFunctions( ) ) );
   const QList<const QgsExpressionNodeFunction *> expFunctions( exp.findNodes<QgsExpressionNodeFunction>() );
   QgsExpressionContext context;
@@ -347,8 +346,7 @@ QSet<QString> QgsValueRelationFieldFormatter::expressionFormAttributes( const QS
   QgsExpression exp( expression );
   std::unique_ptr< QgsExpressionContextScope > scope( QgsExpressionContextUtils::formScope() );
   // List of form function names used in the expression
-  const QSet<QString> formFunctions( scope->functionNames()
-                                     .toSet()
+  const QSet<QString> formFunctions( qgis::listToSet( scope->functionNames() )
                                      .intersect( exp.referencedFunctions( ) ) );
   const QList<const QgsExpressionNodeFunction *> expFunctions( exp.findNodes<QgsExpressionNodeFunction>() );
   QgsExpressionContext context;
diff --git a/src/core/gps/qgsgpsconnectionregistry.cpp b/src/core/gps/qgsgpsconnectionregistry.cpp
index 98ee67c5eac4..0369d7e92a00 100644
--- a/src/core/gps/qgsgpsconnectionregistry.cpp
+++ b/src/core/gps/qgsgpsconnectionregistry.cpp
@@ -35,5 +35,5 @@ void QgsGpsConnectionRegistry::unregisterConnection( QgsGpsConnection *c )
 
 QList< QgsGpsConnection * > QgsGpsConnectionRegistry::connectionList() const
 {
-  return mConnections.toList();
+  return qgis::setToList( mConnections );
 }
diff --git a/src/core/layout/qgslayoutmodel.cpp b/src/core/layout/qgslayoutmodel.cpp
index ae98042cc3df..2c085ef8eaee 100644
--- a/src/core/layout/qgslayoutmodel.cpp
+++ b/src/core/layout/qgslayoutmodel.cpp
@@ -170,7 +170,7 @@ QVariant QgsLayoutModel::data( const QModelIndex &index, int role ) const
       return item->uuid();
     case Qt::UserRole+1:
       //user role stores reference in column object
-      return qVariantFromValue( qobject_cast<QObject *>( item ) );
+      return QVariant::fromValue( qobject_cast<QObject *>( item ) );
 
     case Qt::TextAlignmentRole:
       return Qt::AlignLeft & Qt::AlignVCenter;
@@ -244,11 +244,11 @@ QVariant QgsLayoutModel::headerData( int section, Qt::Orientation orientation, i
     {
       if ( section == Visibility )
       {
-        return qVariantFromValue( QgsApplication::getThemeIcon( QStringLiteral( "/mActionShowAllLayersGray.svg" ) ) );
+        return QVariant::fromValue( QgsApplication::getThemeIcon( QStringLiteral( "/mActionShowAllLayersGray.svg" ) ) );
       }
       else if ( section == LockStatus )
       {
-        return qVariantFromValue( QgsApplication::getThemeIcon( QStringLiteral( "/lockedGray.svg" ) ) );
+        return QVariant::fromValue( QgsApplication::getThemeIcon( QStringLiteral( "/lockedGray.svg" ) ) );
       }
 
       return QVariant();
diff --git a/src/core/providers/memory/qgsmemoryfeatureiterator.cpp b/src/core/providers/memory/qgsmemoryfeatureiterator.cpp
index 6a420eee53c6..20b041e866ee 100644
--- a/src/core/providers/memory/qgsmemoryfeatureiterator.cpp
+++ b/src/core/providers/memory/qgsmemoryfeatureiterator.cpp
@@ -75,7 +75,7 @@ QgsMemoryFeatureIterator::QgsMemoryFeatureIterator( QgsMemoryFeatureSource *sour
   else if ( mRequest.filterType() == QgsFeatureRequest::FilterFids )
   {
     mUsingFeatureIdList = true;
-    mFeatureIdList = mRequest.filterFids().toList();
+    mFeatureIdList = qgis::setToList( mRequest.filterFids() );
   }
   else
   {
diff --git a/src/core/providers/memory/qgsmemoryprovider.cpp b/src/core/providers/memory/qgsmemoryprovider.cpp
index a741adeb33ae..390e43719dae 100644
--- a/src/core/providers/memory/qgsmemoryprovider.cpp
+++ b/src/core/providers/memory/qgsmemoryprovider.cpp
@@ -523,7 +523,7 @@ bool QgsMemoryProvider::renameAttributes( const QgsFieldNameMap &renamedAttribut
 
 bool QgsMemoryProvider::deleteAttributes( const QgsAttributeIds &attributes )
 {
-  QList<int> attrIdx = attributes.toList();
+  QList<int> attrIdx = qgis::setToList( attributes );
   std::sort( attrIdx.begin(), attrIdx.end(), std::greater<int>() );
 
   // delete attributes one-by-one with decreasing index
diff --git a/src/core/providers/ogr/qgsogrfeatureiterator.cpp b/src/core/providers/ogr/qgsogrfeatureiterator.cpp
index ef229ee8fd5e..2d69538fc10f 100644
--- a/src/core/providers/ogr/qgsogrfeatureiterator.cpp
+++ b/src/core/providers/ogr/qgsogrfeatureiterator.cpp
@@ -130,8 +130,8 @@ QgsOgrFeatureIterator::QgsOgrFeatureIterator( QgsOgrFeatureSource *source, bool
   {
     //ensure that all fields required for filter expressions are prepared
     QSet<int> attributeIndexes = request.filterExpression()->referencedAttributeIndexes( mSource->mFields );
-    attributeIndexes += attrs.toSet();
-    attrs = attributeIndexes.toList();
+    attributeIndexes += qgis::listToSet( attrs );
+    attrs = qgis::setToList( attributeIndexes );
     mRequest.setSubsetOfAttributes( attrs );
   }
   // also need attributes required by order by
@@ -143,8 +143,8 @@ QgsOgrFeatureIterator::QgsOgrFeatureIterator( QgsOgrFeatureSource *source, bool
     {
       attributeIndexes << attrIdx;
     }
-    attributeIndexes += attrs.toSet();
-    attrs = attributeIndexes.toList();
+    attributeIndexes += qgis::listToSet( attrs );
+    attrs = qgis::setToList( attributeIndexes );
     mRequest.setSubsetOfAttributes( attrs );
   }
 
diff --git a/src/core/providers/ogr/qgsogrprovider.cpp b/src/core/providers/ogr/qgsogrprovider.cpp
index f3953cd837d9..35e0c719ddc3 100644
--- a/src/core/providers/ogr/qgsogrprovider.cpp
+++ b/src/core/providers/ogr/qgsogrprovider.cpp
@@ -1998,7 +1998,7 @@ bool QgsOgrProvider::deleteAttributes( const QgsAttributeIds &attributes )
     return false;
 
   bool res = true;
-  QList<int> attrsLst = attributes.toList();
+  QList<int> attrsLst = qgis::setToList( attributes );
   // sort in descending order
   std::sort( attrsLst.begin(), attrsLst.end(), std::greater<int>() );
   const auto constAttrsLst = attrsLst;
diff --git a/src/core/qgis.h b/src/core/qgis.h
index 0097e9979cc5..c8090fa0d770 100644
--- a/src/core/qgis.h
+++ b/src/core/qgis.h
@@ -465,6 +465,16 @@ namespace qgis
     return list.toSet();
 #else
     return QSet<T>( list.begin(), list.end() );
+#endif
+  }
+
+  template<class T>
+  QList<T> setToList( const QSet<T> &set )
+  {
+#if QT_VERSION < QT_VERSION_CHECK(5, 14, 0)
+    return set.toList();
+#else
+    return QList<T>( set.begin(), set.end() );
 #endif
   }
 }
diff --git a/src/core/qgscachedfeatureiterator.cpp b/src/core/qgscachedfeatureiterator.cpp
index 9164ec97b634..8c2c4d385559 100644
--- a/src/core/qgscachedfeatureiterator.cpp
+++ b/src/core/qgscachedfeatureiterator.cpp
@@ -53,7 +53,7 @@ QgsCachedFeatureIterator::QgsCachedFeatureIterator( QgsVectorLayerCache *vlCache
       break;
 
     default:
-      mFeatureIds = mVectorLayerCache->mCache.keys().toSet();
+      mFeatureIds = qgis::listToSet( mVectorLayerCache->mCache.keys() );
       break;
   }
 
diff --git a/src/core/qgsdataitem.cpp b/src/core/qgsdataitem.cpp
index d446afa994c4..9590b7792a07 100644
--- a/src/core/qgsdataitem.cpp
+++ b/src/core/qgsdataitem.cpp
@@ -1133,11 +1133,11 @@ QgsDirectoryParamWidget::QgsDirectoryParamWidget( const QString &path, QWidget *
     QString size;
     if ( fi.size() > 1024 )
     {
-      size = size.sprintf( "%.1f KiB", fi.size() / 1024.0 );
+      size = QStringLiteral( "%1 KiB" ).arg( QString::number( fi.size() / 1024.0, 'f', 1 ) );
     }
     else if ( fi.size() > 1.048576e6 )
     {
-      size = size.sprintf( "%.1f MiB", fi.size() / 1.048576e6 );
+      size = QStringLiteral( "%1 MiB" ).arg( QString::number( fi.size() / 1.048576e6, 'f', 1 ) );
     }
     else
     {
diff --git a/src/core/qgsexpressioncontext.cpp b/src/core/qgsexpressioncontext.cpp
index 30a9b690ff53..07b85a867789 100644
--- a/src/core/qgsexpressioncontext.cpp
+++ b/src/core/qgsexpressioncontext.cpp
@@ -408,7 +408,7 @@ QStringList QgsExpressionContext::variableNames() const
   {
     names << scope->variableNames();
   }
-  return names.toSet().toList();
+  return qgis::setToList( qgis::listToSet( names ) );
 }
 
 QStringList QgsExpressionContext::filteredVariableNames() const
@@ -464,7 +464,7 @@ QStringList QgsExpressionContext::functionNames() const
   {
     result << scope->functionNames();
   }
-  result = result.toSet().toList();
+  result = qgis::setToList( qgis::listToSet( result ) );
   result.sort();
   return result;
 }
diff --git a/src/core/qgsmaprendererjob.cpp b/src/core/qgsmaprendererjob.cpp
index bde376085d09..829732e50cdf 100644
--- a/src/core/qgsmaprendererjob.cpp
+++ b/src/core/qgsmaprendererjob.cpp
@@ -111,7 +111,7 @@ bool QgsMapRendererJob::prepareLabelCache() const
     // we may need to clear label cache and re-register labeled features - check for that here
 
     // can we reuse the cached label solution?
-    bool canUseCache = canCache && mCache->dependentLayers( LABEL_CACHE_ID ).toSet() == labeledLayers;
+    bool canUseCache = canCache && qgis::listToSet( mCache->dependentLayers( LABEL_CACHE_ID ) ) == labeledLayers;
     if ( !canUseCache )
     {
       // no - participating layers have changed
diff --git a/src/core/qgsmapsettingsutils.cpp b/src/core/qgsmapsettingsutils.cpp
index 216bd4e5d85c..c5c9d046c564 100644
--- a/src/core/qgsmapsettingsutils.cpp
+++ b/src/core/qgsmapsettingsutils.cpp
@@ -77,7 +77,7 @@ QStringList QgsMapSettingsUtils::containsAdvancedEffects( const QgsMapSettings &
     }
   }
 
-  return layers.toList();
+  return qgis::setToList( layers );
 }
 
 void QgsMapSettingsUtils::worldFileParameters( const QgsMapSettings &mapSettings, double &a, double &b, double &c, double &d, double &e, double &f )
diff --git a/src/core/qgsmapthemecollection.cpp b/src/core/qgsmapthemecollection.cpp
index 09e7d013721c..fed982ea831a 100644
--- a/src/core/qgsmapthemecollection.cpp
+++ b/src/core/qgsmapthemecollection.cpp
@@ -39,7 +39,7 @@ QgsMapThemeCollection::MapThemeLayerRecord QgsMapThemeCollection::createThemeLay
   layerRec.usingCurrentStyle = true;
   layerRec.currentStyle = nodeLayer->layer()->styleManager()->currentStyle();
   layerRec.expandedLayerNode = nodeLayer->isExpanded();
-  layerRec.expandedLegendItems = nodeLayer->customProperty( QStringLiteral( "expandedLegendNodes" ) ).toStringList().toSet();
+  layerRec.expandedLegendItems = qgis::listToSet( nodeLayer->customProperty( QStringLiteral( "expandedLegendNodes" ) ).toStringList() );
 
   // get checked legend items
   bool hasCheckableItems = false;
@@ -176,7 +176,7 @@ void QgsMapThemeCollection::applyThemeToLayer( QgsLayerTreeLayer *nodeLayer, Qgs
   if ( rec.hasExpandedStateInfo() )
   {
     nodeLayer->setExpanded( layerRec.expandedLayerNode );
-    nodeLayer->setCustomProperty( QStringLiteral( "expandedLegendNodes" ), QStringList( layerRec.expandedLegendItems.toList() ) );
+    nodeLayer->setCustomProperty( QStringLiteral( "expandedLegendNodes" ), QStringList( qgis::setToList( layerRec.expandedLegendItems ) ) );
   }
 }
 
diff --git a/src/core/qgstaskmanager.cpp b/src/core/qgstaskmanager.cpp
index bc7ad5543173..ae71205ddbf9 100644
--- a/src/core/qgstaskmanager.cpp
+++ b/src/core/qgstaskmanager.cpp
@@ -511,7 +511,7 @@ QgsTask *QgsTaskManager::task( long id ) const
 QList<QgsTask *> QgsTaskManager::tasks() const
 {
   QMutexLocker ml( mTaskMutex );
-  return mParentTasks.toList();
+  return qgis::setToList( mParentTasks );
 }
 
 int QgsTaskManager::count() const
@@ -654,7 +654,7 @@ QList<QgsTask *> QgsTaskManager::activeTasks() const
   QMutexLocker ml( mTaskMutex );
   QSet< QgsTask * > activeTasks = mActiveTasks;
   activeTasks.intersect( mParentTasks );
-  return activeTasks.toList();
+  return qgis::setToList( activeTasks );
 }
 
 int QgsTaskManager::countActiveTasks() const
diff --git a/src/core/qgsvectorfilewriter.cpp b/src/core/qgsvectorfilewriter.cpp
index 5b579d604162..8c38285a6daf 100644
--- a/src/core/qgsvectorfilewriter.cpp
+++ b/src/core/qgsvectorfilewriter.cpp
@@ -3294,7 +3294,7 @@ QStringList QgsVectorFileWriter::supportedFormatExtensions( const VectorFormatOp
     }
   }
 
-  QStringList extensionList = extensions.toList();
+  QStringList extensionList = qgis::setToList( extensions );
 
   std::sort( extensionList.begin(), extensionList.end(), [options]( const QString & a, const QString & b ) -> bool
   {
diff --git a/src/core/qgsvectorlayer.cpp b/src/core/qgsvectorlayer.cpp
index 99282d1fe89d..516ba318854a 100644
--- a/src/core/qgsvectorlayer.cpp
+++ b/src/core/qgsvectorlayer.cpp
@@ -3170,7 +3170,7 @@ bool QgsVectorLayer::deleteAttributes( const QList<int> &attrs )
   bool deleted = false;
 
   // Remove multiple occurrences of same attribute
-  QList<int> attrList = attrs.toSet().toList();
+  QList<int> attrList = qgis::setToList( qgis::listToSet( attrs ) );
 
   std::sort( attrList.begin(), attrList.end(), std::greater<int>() );
 
@@ -4045,7 +4045,7 @@ QSet<QVariant> QgsVectorLayer::uniqueValues( int index, int limit ) const
         }
       }
 
-      return val.values().toSet();
+      return qgis::listToSet( val.values() );
     }
   }
 
diff --git a/src/core/qgsvectorlayercache.cpp b/src/core/qgsvectorlayercache.cpp
index 180263139f70..2d1ddad09e36 100644
--- a/src/core/qgsvectorlayercache.cpp
+++ b/src/core/qgsvectorlayercache.cpp
@@ -353,7 +353,7 @@ bool QgsVectorLayerCache::canUseCacheForRequest( const QgsFeatureRequest &featur
     }
     case QgsFeatureRequest::FilterFids:
     {
-      if ( mCache.keys().toSet().contains( featureRequest.filterFids() ) )
+      if ( qgis::listToSet( mCache.keys() ).contains( featureRequest.filterFids() ) )
       {
         it = QgsFeatureIterator( new QgsCachedFeatureIterator( this, featureRequest ) );
         return true;
@@ -412,8 +412,8 @@ QgsFeatureIterator QgsVectorLayerCache::getFeatures( const QgsFeatureRequest &fe
       myRequest.setFlags( featureRequest.flags() & ~QgsFeatureRequest::NoGeometry );
 
     // Make sure, all the cached attributes are requested as well
-    QSet<int> attrs = featureRequest.subsetOfAttributes().toSet() + mCachedAttributes.toSet();
-    myRequest.setSubsetOfAttributes( attrs.toList() );
+    QSet<int> attrs = qgis::listToSet( featureRequest.subsetOfAttributes() ) + qgis::listToSet( mCachedAttributes );
+    myRequest.setSubsetOfAttributes( qgis::setToList( attrs ) );
 
     it = QgsFeatureIterator( new QgsCachedFeatureWriterIterator( this, myRequest ) );
   }
diff --git a/src/core/qgsvectorlayereditbuffer.cpp b/src/core/qgsvectorlayereditbuffer.cpp
index 28a898afee36..54ebfde6568a 100644
--- a/src/core/qgsvectorlayereditbuffer.cpp
+++ b/src/core/qgsvectorlayereditbuffer.cpp
@@ -397,7 +397,7 @@ bool QgsVectorLayerEditBuffer::commitChanges( QStringList &commitErrors )
   bool attributesChanged = false;
   if ( !mDeletedAttributeIds.isEmpty() )
   {
-    if ( ( cap & QgsVectorDataProvider::DeleteAttributes ) && provider->deleteAttributes( mDeletedAttributeIds.toSet() ) )
+    if ( ( cap & QgsVectorDataProvider::DeleteAttributes ) && provider->deleteAttributes( qgis::listToSet( mDeletedAttributeIds ) ) )
     {
       commitErrors << tr( "SUCCESS: %n attribute(s) deleted.", "deleted attributes count", mDeletedAttributeIds.size() );
 
diff --git a/src/core/qgsvectorlayerfeatureiterator.cpp b/src/core/qgsvectorlayerfeatureiterator.cpp
index 05f610e30263..f1fedcca0f58 100644
--- a/src/core/qgsvectorlayerfeatureiterator.cpp
+++ b/src/core/qgsvectorlayerfeatureiterator.cpp
@@ -149,8 +149,8 @@ QgsVectorLayerFeatureIterator::QgsVectorLayerFeatureIterator( QgsVectorLayerFeat
     {
       //ensure that all fields required for filter expressions are prepared
       QSet<int> attributeIndexes = mRequest.filterExpression()->referencedAttributeIndexes( mSource->mFields );
-      attributeIndexes += mRequest.subsetOfAttributes().toSet();
-      mRequest.setSubsetOfAttributes( attributeIndexes.toList() );
+      attributeIndexes += qgis::listToSet( mRequest.subsetOfAttributes() );
+      mRequest.setSubsetOfAttributes( qgis::setToList( attributeIndexes ) );
     }
   }
 
@@ -196,7 +196,7 @@ QgsVectorLayerFeatureIterator::QgsVectorLayerFeatureIterator( QgsVectorLayerFeat
       }
     }
 
-    mProviderRequest.setSubsetOfAttributes( providerSubset.toList() );
+    mProviderRequest.setSubsetOfAttributes( qgis::setToList( providerSubset ) );
   }
 
   if ( mProviderRequest.filterType() == QgsFeatureRequest::FilterExpression )
@@ -723,7 +723,7 @@ void QgsVectorLayerFeatureIterator::prepareExpression( int fieldIdx )
   exp->prepare( mExpressionContext.get() );
   const QSet<int> referencedColumns = exp->referencedAttributeIndexes( mSource->fields() );
 
-  QSet<int> requestedAttributes = mRequest.subsetOfAttributes().toSet();
+  QSet<int> requestedAttributes = qgis::listToSet( mRequest.subsetOfAttributes() );
 
   for ( int dependentFieldIdx : referencedColumns )
   {
@@ -738,7 +738,7 @@ void QgsVectorLayerFeatureIterator::prepareExpression( int fieldIdx )
 
   if ( mRequest.flags() & QgsFeatureRequest::SubsetOfAttributes )
   {
-    mRequest.setSubsetOfAttributes( requestedAttributes.toList() );
+    mRequest.setSubsetOfAttributes( qgis::setToList( requestedAttributes ) );
   }
 
   if ( exp->needsGeometry() )
diff --git a/src/core/qgsvectorlayerjoinbuffer.cpp b/src/core/qgsvectorlayerjoinbuffer.cpp
index bd8a04ae3674..15029017c1f8 100644
--- a/src/core/qgsvectorlayerjoinbuffer.cpp
+++ b/src/core/qgsvectorlayerjoinbuffer.cpp
@@ -221,7 +221,7 @@ void QgsVectorLayerJoinBuffer::updateFields( QgsFields &fields )
     if ( joinIt->hasSubset() )
     {
       const QStringList subsetNames = QgsVectorLayerJoinInfo::joinFieldNamesSubset( *joinIt );
-      subset = QSet<QString>::fromList( subsetNames );
+      subset = qgis::listToSet( subsetNames );
     }
 
     if ( joinIt->prefix().isNull() )
diff --git a/src/core/symbology/qgscategorizedsymbolrenderer.cpp b/src/core/symbology/qgscategorizedsymbolrenderer.cpp
index 1fd94bc98133..6acf6def579e 100644
--- a/src/core/symbology/qgscategorizedsymbolrenderer.cpp
+++ b/src/core/symbology/qgscategorizedsymbolrenderer.cpp
@@ -1121,7 +1121,7 @@ int QgsCategorizedSymbolRenderer::matchToSymbols( QgsStyle *style, const QgsSymb
 
   int matched = 0;
   unmatchedSymbols = style->symbolNames();
-  const QSet< QString > allSymbolNames = unmatchedSymbols.toSet();
+  const QSet< QString > allSymbolNames = qgis::listToSet( unmatchedSymbols );
 
   const QRegularExpression tolerantMatchRe( QStringLiteral( "[^\\w\\d ]" ), QRegularExpression::UseUnicodePropertiesOption );
 
diff --git a/src/core/symbology/qgsrulebasedrenderer.cpp b/src/core/symbology/qgsrulebasedrenderer.cpp
index d318889bec07..96c3d8ab7dd9 100644
--- a/src/core/symbology/qgsrulebasedrenderer.cpp
+++ b/src/core/symbology/qgsrulebasedrenderer.cpp
@@ -951,7 +951,7 @@ void QgsRuleBasedRenderer::startRender( QgsRenderContext &context, const QgsFiel
   mRootRule->startRender( context, fields, mFilter );
 
   QSet<int> symbolZLevelsSet = mRootRule->collectZLevels();
-  QList<int> symbolZLevels = symbolZLevelsSet.toList();
+  QList<int> symbolZLevels = qgis::setToList( symbolZLevelsSet );
   std::sort( symbolZLevels.begin(), symbolZLevels.end() );
 
   // create mapping from unnormalized levels [unlimited range] to normalized levels [0..N-1]
diff --git a/src/core/symbology/qgsstyle.cpp b/src/core/symbology/qgsstyle.cpp
index 170eb27cd407..1294b8e03d1f 100644
--- a/src/core/symbology/qgsstyle.cpp
+++ b/src/core/symbology/qgsstyle.cpp
@@ -1524,7 +1524,7 @@ QStringList QgsStyle::findSymbols( StyleEntity type, const QString &qword )
     symbols << statement.columnAsText( 0 );
   }
 
-  return symbols.toList();
+  return qgis::setToList( symbols );
 }
 
 bool QgsStyle::tagSymbol( StyleEntity type, const QString &symbol, const QStringList &tags )
@@ -2208,7 +2208,7 @@ QStringList QgsStyle::symbolsOfSmartgroup( StyleEntity type, int id )
   }
 
   // return sorted, unique list
-  QStringList unique = symbols.toSet().toList();
+  QStringList unique = qgis::setToList( qgis::listToSet( symbols ) );
   std::sort( unique.begin(), unique.end() );
   return unique;
 }
diff --git a/src/core/symbology/qgssymbollayerutils.cpp b/src/core/symbology/qgssymbollayerutils.cpp
index 8c51dead0ed9..978d0b50cc24 100644
--- a/src/core/symbology/qgssymbollayerutils.cpp
+++ b/src/core/symbology/qgssymbollayerutils.cpp
@@ -75,9 +75,7 @@ QColor QgsSymbolLayerUtils::decodeColor( const QString &str )
 
 QString QgsSymbolLayerUtils::encodeSldAlpha( int alpha )
 {
-  QString result;
-  result.sprintf( "%.2g", alpha / 255.0 );
-  return result;
+  return QString::number( alpha / 255.0, 'g', 2 );
 }
 
 int QgsSymbolLayerUtils::decodeSldAlpha( const QString &str )
diff --git a/src/core/vectortile/qgsvectortileutils.cpp b/src/core/vectortile/qgsvectortileutils.cpp
index cd7bb747fa8e..b855bb1b3d94 100644
--- a/src/core/vectortile/qgsvectortileutils.cpp
+++ b/src/core/vectortile/qgsvectortileutils.cpp
@@ -51,7 +51,7 @@ QPolygon QgsVectorTileUtils::tilePolygon( QgsTileXYZ id, const QgsCoordinateTran
 QgsFields QgsVectorTileUtils::makeQgisFields( QSet<QString> flds )
 {
   QgsFields fields;
-  QStringList fieldsSorted = flds.toList();
+  QStringList fieldsSorted = qgis::setToList( flds );
   std::sort( fieldsSorted.begin(), fieldsSorted.end() );
   for ( const QString &fieldName : qgis::as_const( fieldsSorted ) )
   {
@@ -80,7 +80,7 @@ QgsVectorLayer *QgsVectorTileUtils::makeVectorLayerForTile( QgsVectorTileLayer *
 {
   QgsVectorTileMVTDecoder decoder;
   decoder.decode( tileID, mvt->getRawTile( tileID ) );
-  QSet<QString> fieldNames = QSet<QString>::fromList( decoder.layerFieldNames( layerName ) );
+  QSet<QString> fieldNames = qgis::listToSet( decoder.layerFieldNames( layerName ) );
   fieldNames << QStringLiteral( "_geom_type" );
   QMap<QString, QgsFields> perLayerFields;
   QgsFields fields = QgsVectorTileUtils::makeQgisFields( fieldNames );
diff --git a/src/gui/attributetable/qgsattributetableview.cpp b/src/gui/attributetable/qgsattributetableview.cpp
index 605f4547240a..3740fb96127f 100644
--- a/src/gui/attributetable/qgsattributetableview.cpp
+++ b/src/gui/attributetable/qgsattributetableview.cpp
@@ -239,7 +239,7 @@ QWidget *QgsAttributeTableView::createActionWidget( QgsFeatureId fid )
     action->setData( "map_layer_action" );
     action->setToolTip( mapLayerAction->text() );
     action->setProperty( "fid", fid );
-    action->setProperty( "action", qVariantFromValue( qobject_cast<QObject *>( mapLayerAction ) ) );
+    action->setProperty( "action", QVariant::fromValue( qobject_cast<QObject *>( mapLayerAction ) ) );
     connect( action, &QAction::triggered, this, &QgsAttributeTableView::actionTriggered );
     actionList << action;
 
diff --git a/src/gui/editorwidgets/qgsrelationreferencewidget.cpp b/src/gui/editorwidgets/qgsrelationreferencewidget.cpp
index f87b06bf0f55..c337ac17f24d 100644
--- a/src/gui/editorwidgets/qgsrelationreferencewidget.cpp
+++ b/src/gui/editorwidgets/qgsrelationreferencewidget.cpp
@@ -516,7 +516,7 @@ void QgsRelationReferenceWidget::init()
         cb->setProperty( "Field", fieldName );
         cb->setProperty( "FieldAlias", mReferencedLayer->attributeDisplayName( idx ) );
         mFilterComboBoxes << cb;
-        QVariantList uniqueValues = mReferencedLayer->uniqueValues( idx ).toList();
+        QVariantList uniqueValues = qgis::setToList( mReferencedLayer->uniqueValues( idx ) );
         cb->addItem( mReferencedLayer->attributeDisplayName( idx ) );
         QVariant nullValue = QgsApplication::nullRepresentation();
         cb->addItem( nullValue.toString(), QVariant( mReferencedLayer->fields().at( idx ).type() ) );
diff --git a/src/gui/layertree/qgslayertreeview.cpp b/src/gui/layertree/qgslayertreeview.cpp
index 10b3f90e9457..ce85562a76ea 100644
--- a/src/gui/layertree/qgslayertreeview.cpp
+++ b/src/gui/layertree/qgslayertreeview.cpp
@@ -299,7 +299,7 @@ void QgsLayerTreeView::onCustomPropertyChanged( QgsLayerTreeNode *node, const QS
   if ( key != QStringLiteral( "expandedLegendNodes" ) || !QgsLayerTree::isLayer( node ) )
     return;
 
-  QSet<QString> expandedLegendNodes = node->customProperty( QStringLiteral( "expandedLegendNodes" ) ).toStringList().toSet();
+  QSet<QString> expandedLegendNodes = qgis::listToSet( node->customProperty( QStringLiteral( "expandedLegendNodes" ) ).toStringList() );
 
   const QList<QgsLayerTreeModelLegendNode *> legendNodes = layerTreeModel()->layerLegendNodes( QgsLayerTree::toLayer( node ), true );
   for ( QgsLayerTreeModelLegendNode *legendNode : legendNodes )
@@ -412,7 +412,7 @@ QList<QgsMapLayer *> QgsLayerTreeView::selectedLayersRecursive() const
 {
   const QList<QgsLayerTreeNode *> nodes = layerTreeModel()->indexes2nodes( selectionModel()->selectedIndexes(), false );
   QSet<QgsMapLayer *> layersSet = QgsLayerTreeUtils::collectMapLayersRecursive( nodes );
-  return layersSet.toList();
+  return qgis::setToList( layersSet );
 }
 
 void QgsLayerTreeView::addIndicator( QgsLayerTreeNode *node, QgsLayerTreeViewIndicator *indicator )
diff --git a/src/gui/processing/qgsprocessingenummodelerwidget.cpp b/src/gui/processing/qgsprocessingenummodelerwidget.cpp
index 7ac30ff9a831..699be7b1bc70 100644
--- a/src/gui/processing/qgsprocessingenummodelerwidget.cpp
+++ b/src/gui/processing/qgsprocessingenummodelerwidget.cpp
@@ -60,7 +60,7 @@ void QgsProcessingEnumModelerWidget::removeItems( const bool removeAll )
     for ( const QModelIndex &i : selected )
       rows << i.row();
 
-    QList< int > rowsToDelete = rows.toList();
+    QList< int > rowsToDelete = qgis::setToList( rows );
     std::sort( rowsToDelete.begin(), rowsToDelete.end(), std::greater<int>() );
 
     mItemList->setUpdatesEnabled( false );
diff --git a/src/gui/processing/qgsprocessingmatrixparameterdialog.cpp b/src/gui/processing/qgsprocessingmatrixparameterdialog.cpp
index 00ca298320a7..4ce5434817b8 100644
--- a/src/gui/processing/qgsprocessingmatrixparameterdialog.cpp
+++ b/src/gui/processing/qgsprocessingmatrixparameterdialog.cpp
@@ -102,7 +102,7 @@ void QgsProcessingMatrixParameterPanelWidget::deleteRow()
   for ( const QModelIndex &i : selected )
     rows << i.row();
 
-  QList< int > rowsToDelete = rows.toList();
+  QList< int > rowsToDelete = qgis::setToList( rows );
   std::sort( rowsToDelete.begin(), rowsToDelete.end(), std::greater<int>() );
   mTblView->setUpdatesEnabled( false );
   for ( int i : qgis::as_const( rowsToDelete ) )
diff --git a/src/gui/qgscolorschemelist.cpp b/src/gui/qgscolorschemelist.cpp
index 408ff0fecd57..d6abd35a402f 100644
--- a/src/gui/qgscolorschemelist.cpp
+++ b/src/gui/qgscolorschemelist.cpp
@@ -81,7 +81,7 @@ void QgsColorSchemeList::removeSelection()
     rows << index.row();
   }
   //remove duplicates
-  QList<int> rowsToRemove = QList<int>::fromSet( rows.toSet() );
+  QList<int> rowsToRemove = qgis::setToList( qgis::listToSet( rows ) );
 
   //remove rows in descending order
   std::sort( rowsToRemove.begin(), rowsToRemove.end(), std::greater<int>() );
@@ -124,7 +124,7 @@ void QgsColorSchemeList::copyColors()
     rows << index.row();
   }
   //remove duplicates
-  QList<int> rowsToCopy = QList<int>::fromSet( rows.toSet() );
+  QList<int> rowsToCopy = qgis::setToList( qgis::listToSet( rows ) );
 
   QgsNamedColorList colorsToCopy;
   const auto constRowsToCopy = rowsToCopy;
@@ -208,7 +208,7 @@ void QgsColorSchemeList::keyPressEvent( QKeyEvent *event )
       rows << index.row();
     }
     //remove duplicates
-    QList<int> rowsToRemove = QList<int>::fromSet( rows.toSet() );
+    QList<int> rowsToRemove = qgis::setToList( qgis::listToSet( rows ) );
 
     //remove rows in descending order
     std::sort( rowsToRemove.begin(), rowsToRemove.end(), std::greater<int>() );
diff --git a/src/gui/qgsconfigureshortcutsdialog.cpp b/src/gui/qgsconfigureshortcutsdialog.cpp
index 288571458efe..fc514c19e436 100644
--- a/src/gui/qgsconfigureshortcutsdialog.cpp
+++ b/src/gui/qgsconfigureshortcutsdialog.cpp
@@ -93,7 +93,7 @@ void QgsConfigureShortcutsDialog::populateActions()
     lst << actionText << sequence;
     QTreeWidgetItem *item = new QTreeWidgetItem( lst );
     item->setIcon( 0, icon );
-    item->setData( 0, Qt::UserRole, qVariantFromValue( obj ) );
+    item->setData( 0, Qt::UserRole, QVariant::fromValue( obj ) );
     items.append( item );
   }
 
diff --git a/src/gui/qgsexpressionbuilderwidget.cpp b/src/gui/qgsexpressionbuilderwidget.cpp
index 84d20f2d8e3c..8e124d3dc579 100644
--- a/src/gui/qgsexpressionbuilderwidget.cpp
+++ b/src/gui/qgsexpressionbuilderwidget.cpp
@@ -524,7 +524,7 @@ void QgsExpressionBuilderWidget::fillFieldValues( const QString &fieldName, int
   }
   else
   {
-    values = mLayer->uniqueValues( fieldIndex, countLimit ).toList();
+    values = qgis::setToList( mLayer->uniqueValues( fieldIndex, countLimit ) );
   }
   std::sort( values.begin(), values.end() );
 
diff --git a/src/gui/qgsfieldmappingmodel.cpp b/src/gui/qgsfieldmappingmodel.cpp
index 27e08a638623..2ba69f1d2214 100644
--- a/src/gui/qgsfieldmappingmodel.cpp
+++ b/src/gui/qgsfieldmappingmodel.cpp
@@ -359,9 +359,9 @@ void QgsFieldMappingModel::setDestinationFields( const QgsFields &destinationFie
       const QgsExpression exp { f.expression };
       // if it's source field
       if ( exp.isField() &&
-           mSourceFields.names().contains( exp.referencedColumns().toList().first() ) )
+           mSourceFields.names().contains( qgis::setToList( exp.referencedColumns() ).first() ) )
       {
-        usedFields.push_back( exp.referencedColumns().toList().first() );
+        usedFields.push_back( qgis::setToList( exp.referencedColumns() ).first() );
       }
     }
     else
diff --git a/src/gui/qgsmaptoolidentify.cpp b/src/gui/qgsmaptoolidentify.cpp
index eadb6b603495..a59915ce4317 100644
--- a/src/gui/qgsmaptoolidentify.cpp
+++ b/src/gui/qgsmaptoolidentify.cpp
@@ -408,7 +408,7 @@ bool QgsMapToolIdentify::identifyVectorTileLayer( QList<QgsMapToolIdentify::Iden
         const QStringList layerNames = decoder.layers();
         for ( const QString &layerName : layerNames )
         {
-          QSet<QString> fieldNames = QSet<QString>::fromList( decoder.layerFieldNames( layerName ) );
+          QSet<QString> fieldNames = qgis::listToSet( decoder.layerFieldNames( layerName ) );
           perLayerFields[layerName] = QgsVectorTileUtils::makeQgisFields( fieldNames );
         }
 
diff --git a/src/gui/qgsowssourceselect.cpp b/src/gui/qgsowssourceselect.cpp
index 6bf01e4ed528..a6ca03af9bd9 100644
--- a/src/gui/qgsowssourceselect.cpp
+++ b/src/gui/qgsowssourceselect.cpp
@@ -421,7 +421,7 @@ void QgsOWSSourceSelect::mLayersTreeWidget_itemSelectionChanged()
 void QgsOWSSourceSelect::populateCrs()
 {
   clearCrs();
-  mSelectedLayersCRSs = selectedLayersCrses().toSet();
+  mSelectedLayersCRSs = qgis::listToSet( selectedLayersCrses() );
   mCRSLabel->setText( tr( "Coordinate Reference System (%n available)", "crs count", mSelectedLayersCRSs.count() ) + ':' );
 
   mChangeCRSButton->setDisabled( mSelectedLayersCRSs.isEmpty() );
diff --git a/src/gui/qgsquerybuilder.cpp b/src/gui/qgsquerybuilder.cpp
index 69d3dd27c256..350272457c70 100644
--- a/src/gui/qgsquerybuilder.cpp
+++ b/src/gui/qgsquerybuilder.cpp
@@ -141,7 +141,7 @@ void QgsQueryBuilder::fillValues( int idx, int limit )
   mModelValues->clear();
 
   // determine the field type
-  QList<QVariant> values = mLayer->uniqueValues( idx, limit ).toList();
+  QList<QVariant> values = qgis::setToList( mLayer->uniqueValues( idx, limit ) );
   std::sort( values.begin(), values.end() );
 
   QString nullValue = QgsApplication::nullRepresentation();
diff --git a/src/gui/symbology/qgscategorizedsymbolrendererwidget.cpp b/src/gui/symbology/qgscategorizedsymbolrendererwidget.cpp
index c5dae69f7956..d41109d71bac 100644
--- a/src/gui/symbology/qgscategorizedsymbolrendererwidget.cpp
+++ b/src/gui/symbology/qgscategorizedsymbolrendererwidget.cpp
@@ -786,7 +786,7 @@ void QgsCategorizedSymbolRendererWidget::addCategories()
   }
   else
   {
-    uniqueValues = mLayer->uniqueValues( idx ).toList();
+    uniqueValues = qgis::setToList( mLayer->uniqueValues( idx ) );
   }
 
   // ask to abort if too many classes
diff --git a/src/gui/vector/qgsattributeactiondialog.cpp b/src/gui/vector/qgsattributeactiondialog.cpp
index 35b5f1250e0d..1833864e6434 100644
--- a/src/gui/vector/qgsattributeactiondialog.cpp
+++ b/src/gui/vector/qgsattributeactiondialog.cpp
@@ -133,7 +133,7 @@ void QgsAttributeActionDialog::insertRow( int row, const QgsAction &action )
   // Scopes
   item = new QTableWidgetItem();
   item->setFlags( item->flags() & ~( Qt::ItemIsEditable ) );
-  QStringList actionScopes = action.actionScopes().toList();
+  QStringList actionScopes = qgis::setToList( action.actionScopes() );
   std::sort( actionScopes.begin(), actionScopes.end() );
   item->setText( actionScopes.join( QStringLiteral( ", " ) ) );
   item->setData( Qt::UserRole, QVariant::fromValue<QSet<QString>>( action.actionScopes() ) );
@@ -355,7 +355,7 @@ void QgsAttributeActionDialog::itemDoubleClicked( QTableWidgetItem *item )
     mAttributeActionTable->item( row, EnabledOnlyWhenEditable )->setCheckState( actionProperties.isEnabledOnlyWhenEditable() ? Qt::Checked : Qt::Unchecked );
 
     QTableWidgetItem *item = mAttributeActionTable->item( row, ActionScopes );
-    QStringList actionScopes = actionProperties.actionScopes().toList();
+    QStringList actionScopes = qgis::setToList( actionProperties.actionScopes() );
     std::sort( actionScopes.begin(), actionScopes.end() );
     item->setText( actionScopes.join( QStringLiteral( ", " ) ) );
     item->setData( Qt::UserRole, QVariant::fromValue<QSet<QString>>( actionProperties.actionScopes() ) );
diff --git a/src/gui/vector/qgswmsdimensiondialog.cpp b/src/gui/vector/qgswmsdimensiondialog.cpp
index c9032574ec91..44e130087c63 100644
--- a/src/gui/vector/qgswmsdimensiondialog.cpp
+++ b/src/gui/vector/qgswmsdimensiondialog.cpp
@@ -192,7 +192,7 @@ void QgsWmsDimensionDialog::fieldChanged()
     int currentEndFieldIndexOf = mLayer->fields().indexOf( currentEndFieldName );
     uniqueValues.unite( mLayer->uniqueValues( currentEndFieldIndexOf ) );
   }
-  QList<QVariant> values = uniqueValues.toList();
+  QList<QVariant> values = qgis::setToList( uniqueValues );
   std::sort( values.begin(), values.end() );
 
   mReferenceValueComboBox->clear();
diff --git a/src/providers/arcgisrest/qgsafsfeatureiterator.cpp b/src/providers/arcgisrest/qgsafsfeatureiterator.cpp
index e0bb07b6038e..db71e90ec374 100644
--- a/src/providers/arcgisrest/qgsafsfeatureiterator.cpp
+++ b/src/providers/arcgisrest/qgsafsfeatureiterator.cpp
@@ -83,7 +83,7 @@ QgsAfsFeatureIterator::QgsAfsFeatureIterator( QgsAfsFeatureSource *source, bool
     mDeferredFeaturesInFilterRectCheck = true;
   }
 
-  mFeatureIdList = requestIds.toList();
+  mFeatureIdList = qgis::setToList( requestIds );
   std::sort( mFeatureIdList.begin(), mFeatureIdList.end() );
   mRemainingFeatureIds = mFeatureIdList;
   if ( !mRemainingFeatureIds.empty() )
@@ -113,13 +113,13 @@ bool QgsAfsFeatureIterator::fetchFeature( QgsFeature &f )
     QgsFeatureIds featuresInRect = mSource->sharedData()->getFeatureIdsInExtent( mFilterRect, mInterruptionChecker );
     if ( !mFeatureIdList.isEmpty() )
     {
-      QgsFeatureIds requestIds = mFeatureIdList.toSet();
+      QgsFeatureIds requestIds = qgis::listToSet( mFeatureIdList );
       requestIds.intersect( featuresInRect );
-      mFeatureIdList = requestIds.toList();
+      mFeatureIdList = qgis::setToList( requestIds );
     }
     else
     {
-      mFeatureIdList = featuresInRect.toList();
+      mFeatureIdList = qgis::setToList( featuresInRect );
     }
     if ( mFeatureIdList.empty() )
     {
diff --git a/src/providers/arcgisrest/qgsamsprovider.cpp b/src/providers/arcgisrest/qgsamsprovider.cpp
index 176904557118..8df422fc6275 100644
--- a/src/providers/arcgisrest/qgsamsprovider.cpp
+++ b/src/providers/arcgisrest/qgsamsprovider.cpp
@@ -883,7 +883,7 @@ QgsRasterIdentifyResult QgsAmsProvider::identify( const QgsPointXY &point, QgsRa
       params[QStringLiteral( "featureType" )] = attributesMap[resultMap[QStringLiteral( "displayFieldName" )].toString()].toString();
       store.setParams( params );
       store.addFeature( feature );
-      entries.insert( entries.size(), qVariantFromValue( QList<QgsFeatureStore>() << store ) );
+      entries.insert( entries.size(), QVariant::fromValue( QList<QgsFeatureStore>() << store ) );
     }
   }
   return QgsRasterIdentifyResult( format, entries );
diff --git a/src/providers/db2/qgsdb2featureiterator.cpp b/src/providers/db2/qgsdb2featureiterator.cpp
index a01cfdae371b..b0b488604f68 100644
--- a/src/providers/db2/qgsdb2featureiterator.cpp
+++ b/src/providers/db2/qgsdb2featureiterator.cpp
@@ -89,8 +89,8 @@ void QgsDb2FeatureIterator::BuildStatement( const QgsFeatureRequest &request )
   {
     //ensure that all fields required for filter expressions are prepared
     QSet<int> attributeIndexes = request.filterExpression()->referencedAttributeIndexes( mSource->mFields );
-    attributeIndexes += attrs.toSet();
-    attrs = attributeIndexes.toList();
+    attributeIndexes += qgis::listToSet( attrs );
+    attrs = qgis::setToList( attributeIndexes );
   }
 
   const auto constAttrs = attrs;
diff --git a/src/providers/delimitedtext/qgsdelimitedtextfeatureiterator.cpp b/src/providers/delimitedtext/qgsdelimitedtextfeatureiterator.cpp
index 2348f2abac81..abaaddede92b 100644
--- a/src/providers/delimitedtext/qgsdelimitedtextfeatureiterator.cpp
+++ b/src/providers/delimitedtext/qgsdelimitedtextfeatureiterator.cpp
@@ -154,8 +154,8 @@ QgsDelimitedTextFeatureIterator::QgsDelimitedTextFeatureIterator( QgsDelimitedTe
     QgsAttributeList attrs = request.subsetOfAttributes();
     //ensure that all fields required for filter expressions are prepared
     QSet<int> attributeIndexes = request.filterExpression()->referencedAttributeIndexes( mSource->mFields );
-    attributeIndexes += attrs.toSet();
-    mRequest.setSubsetOfAttributes( attributeIndexes.toList() );
+    attributeIndexes += qgis::listToSet( attrs );
+    mRequest.setSubsetOfAttributes( qgis::setToList( attributeIndexes ) );
   }
   // also need attributes required by order by
   if ( mRequest.flags() & QgsFeatureRequest::SubsetOfAttributes && !mRequest.orderBy().isEmpty() )
diff --git a/src/providers/gpx/gpsdata.cpp b/src/providers/gpx/gpsdata.cpp
index 332bfa42e9f4..ae45feec7edf 100644
--- a/src/providers/gpx/gpsdata.cpp
+++ b/src/providers/gpx/gpsdata.cpp
@@ -288,7 +288,7 @@ QgsGpsData::TrackIterator QgsGpsData::addTrack( const QgsTrack &trk )
 
 void QgsGpsData::removeWaypoints( const QgsFeatureIds &ids )
 {
-  QList<QgsFeatureId> ids2 = ids.toList();
+  QList<QgsFeatureId> ids2 = qgis::setToList( ids );
   std::sort( ids2.begin(), ids2.end() );
   QList<QgsFeatureId>::const_iterator iter = ids2.constBegin();
   WaypointIterator wIter;
@@ -309,7 +309,7 @@ void QgsGpsData::removeWaypoints( const QgsFeatureIds &ids )
 
 void QgsGpsData::removeRoutes( const QgsFeatureIds &ids )
 {
-  QList<QgsFeatureId> ids2 = ids.toList();
+  QList<QgsFeatureId> ids2 = qgis::setToList( ids );
   std::sort( ids2.begin(), ids2.end() );
   QList<QgsFeatureId>::const_iterator iter = ids2.constBegin();
   RouteIterator rIter;
@@ -329,7 +329,7 @@ void QgsGpsData::removeRoutes( const QgsFeatureIds &ids )
 
 void QgsGpsData::removeTracks( const QgsFeatureIds &ids )
 {
-  QList<QgsFeatureId> ids2 = ids.toList();
+  QList<QgsFeatureId> ids2 = qgis::setToList( ids );
   std::sort( ids2.begin(), ids2.end() );
   QList<QgsFeatureId>::const_iterator iter = ids2.constBegin();
   TrackIterator tIter;
diff --git a/src/providers/mssql/qgsmssqlfeatureiterator.cpp b/src/providers/mssql/qgsmssqlfeatureiterator.cpp
index d97d10c35128..4f4235fb0f55 100644
--- a/src/providers/mssql/qgsmssqlfeatureiterator.cpp
+++ b/src/providers/mssql/qgsmssqlfeatureiterator.cpp
@@ -108,8 +108,8 @@ void QgsMssqlFeatureIterator::BuildStatement( const QgsFeatureRequest &request )
     {
       //ensure that all fields required for filter expressions are prepared
       QSet<int> attributeIndexes = request.filterExpression()->referencedAttributeIndexes( mSource->mFields );
-      attributeIndexes += attrs.toSet();
-      attrs = attributeIndexes.toList();
+      attributeIndexes += qgis::listToSet( attrs );
+      attrs = qgis::setToList( attributeIndexes );
     }
 
     // ensure that all attributes required for order by are fetched
diff --git a/src/providers/postgres/qgspgtablemodel.cpp b/src/providers/postgres/qgspgtablemodel.cpp
index bd6cf3c5df24..d006ce163988 100644
--- a/src/providers/postgres/qgspgtablemodel.cpp
+++ b/src/providers/postgres/qgspgtablemodel.cpp
@@ -353,8 +353,8 @@ bool QgsPgTableModel::setData( const QModelIndex &idx, const QVariant &value, in
     QStringList pkCols = idx.sibling( idx.row(), DbtmPkCol ).data( Qt::UserRole + 1 ).toStringList();
     if ( tip.isEmpty() && !pkCols.isEmpty() )
     {
-      QSet<QString> s0( idx.sibling( idx.row(), DbtmPkCol ).data( Qt::UserRole + 2 ).toStringList().toSet() );
-      QSet<QString> s1( pkCols.toSet() );
+      QSet<QString> s0( qgis::listToSet( idx.sibling( idx.row(), DbtmPkCol ).data( Qt::UserRole + 2 ).toStringList() ) );
+      QSet<QString> s1( qgis::listToSet( pkCols ) );
       if ( !s0.intersects( s1 ) )
         tip = tr( "Select columns in the '%1' column that uniquely identify features of this layer" ).arg( tr( "Feature id" ) );
     }
@@ -430,8 +430,8 @@ QString QgsPgTableModel::layerURI( const QModelIndex &index, const QString &conn
   }
 
   QStandardItem *pkItem = itemFromIndex( index.sibling( index.row(), DbtmPkCol ) );
-  QSet<QString> s0( pkItem->data( Qt::UserRole + 1 ).toStringList().toSet() );
-  QSet<QString> s1( pkItem->data( Qt::UserRole + 2 ).toStringList().toSet() );
+  QSet<QString> s0( qgis::listToSet( pkItem->data( Qt::UserRole + 1 ).toStringList() ) );
+  QSet<QString> s1( qgis::listToSet( pkItem->data( Qt::UserRole + 2 ).toStringList() ) );
   if ( !s0.isEmpty() && !s0.intersects( s1 ) )
   {
     // no valid primary candidate selected
@@ -471,7 +471,7 @@ QString QgsPgTableModel::layerURI( const QModelIndex &index, const QString &conn
     cols << QgsPostgresConn::quotedIdentifier( col );
   }
 
-  QgsSettings().setValue( QStringLiteral( "/PostgreSQL/connections/%1/keys/%2/%3" ).arg( mConnName, schemaName, tableName ), QVariant( s1.toList() ) );
+  QgsSettings().setValue( QStringLiteral( "/PostgreSQL/connections/%1/keys/%2/%3" ).arg( mConnName, schemaName, tableName ), QVariant( qgis::setToList( s1 ) ) );
 
   uri.setDataSource( schemaName, tableName, geomColumnName, sql, cols.join( ',' ) );
   uri.setUseEstimatedMetadata( useEstimatedMetadata );
diff --git a/src/providers/postgres/qgspostgresfeatureiterator.cpp b/src/providers/postgres/qgspostgresfeatureiterator.cpp
index 1f0a4a1c0fa5..aebd7b42bfba 100644
--- a/src/providers/postgres/qgspostgresfeatureiterator.cpp
+++ b/src/providers/postgres/qgspostgresfeatureiterator.cpp
@@ -108,8 +108,8 @@ QgsPostgresFeatureIterator::QgsPostgresFeatureIterator( QgsPostgresFeatureSource
       QgsAttributeList attrs = mRequest.subsetOfAttributes();
       //ensure that all fields required for filter expressions are prepared
       QSet<int> attributeIndexes = request.filterExpression()->referencedAttributeIndexes( mSource->mFields );
-      attributeIndexes += attrs.toSet();
-      mRequest.setSubsetOfAttributes( attributeIndexes.toList() );
+      attributeIndexes += qgis::listToSet( attrs );
+      mRequest.setSubsetOfAttributes( qgis::setToList( attributeIndexes ) );
     }
     mFilterRequiresGeometry = request.filterExpression()->needsGeometry();
 
diff --git a/src/providers/postgres/qgspostgresprovider.cpp b/src/providers/postgres/qgspostgresprovider.cpp
index bb1e0a296de0..b53fb688aea7 100644
--- a/src/providers/postgres/qgspostgresprovider.cpp
+++ b/src/providers/postgres/qgspostgresprovider.cpp
@@ -3284,8 +3284,8 @@ bool QgsPostgresProvider::changeFeatures( const QgsChangedAttributesMap &attr_ma
   {
     conn->begin();
 
-    QgsFeatureIds ids( attr_map.keys().toSet() );
-    ids |= geometry_map.keys().toSet();
+    QgsFeatureIds ids( qgis::listToSet( attr_map.keys() ) );
+    ids |= qgis::listToSet( geometry_map.keys() );
 
     // cycle through the features
     const auto constIds = ids;
diff --git a/src/providers/spatialite/qgsspatialitefeatureiterator.cpp b/src/providers/spatialite/qgsspatialitefeatureiterator.cpp
index be65bd462bfe..2ba6bd04076c 100644
--- a/src/providers/spatialite/qgsspatialitefeatureiterator.cpp
+++ b/src/providers/spatialite/qgsspatialitefeatureiterator.cpp
@@ -115,8 +115,8 @@ QgsSpatiaLiteFeatureIterator::QgsSpatiaLiteFeatureIterator( QgsSpatiaLiteFeature
       QgsAttributeList attrs = request.subsetOfAttributes();
       //ensure that all fields required for filter expressions are prepared
       QSet<int> attributeIndexes = request.filterExpression()->referencedAttributeIndexes( mSource->mFields );
-      attributeIndexes += attrs.toSet();
-      mRequest.setSubsetOfAttributes( attributeIndexes.toList() );
+      attributeIndexes += qgis::listToSet( attrs );
+      mRequest.setSubsetOfAttributes( qgis::setToList( attributeIndexes ) );
     }
     if ( request.filterExpression()->needsGeometry() )
     {
@@ -211,8 +211,8 @@ QgsSpatiaLiteFeatureIterator::QgsSpatiaLiteFeatureIterator( QgsSpatiaLiteFeature
       {
         attributeIndexes << attrIdx;
       }
-      attributeIndexes += mRequest.subsetOfAttributes().toSet();
-      mRequest.setSubsetOfAttributes( attributeIndexes.toList() );
+      attributeIndexes += qgis::listToSet( mRequest.subsetOfAttributes() );
+      mRequest.setSubsetOfAttributes( qgis::setToList( attributeIndexes ) );
     }
 
     // preparing the SQL statement
diff --git a/src/providers/wcs/qgswcscapabilities.cpp b/src/providers/wcs/qgswcscapabilities.cpp
index 2481e9c84687..d52f74e6891e 100644
--- a/src/providers/wcs/qgswcscapabilities.cpp
+++ b/src/providers/wcs/qgswcscapabilities.cpp
@@ -1122,7 +1122,7 @@ bool QgsWcsCapabilities::parseDescribeCoverageDom11( QByteArray const &xml, QgsW
   }
   if ( !authids.isEmpty() )
   {
-    coverage->supportedCrs = authids.toList();
+    coverage->supportedCrs = qgis::setToList( authids );
   }
 
   coverage->described = true;
diff --git a/src/providers/wfs/qgsbackgroundcachedfeatureiterator.cpp b/src/providers/wfs/qgsbackgroundcachedfeatureiterator.cpp
index c9bbdf3c3d3c..be86dd982320 100644
--- a/src/providers/wfs/qgsbackgroundcachedfeatureiterator.cpp
+++ b/src/providers/wfs/qgsbackgroundcachedfeatureiterator.cpp
@@ -524,8 +524,7 @@ void QgsBackgroundCachedFeatureIterator::featureReceivedSynchronous( const QVect
   }
   if ( !mWriterFile && mWriterByteArray.size() > mWriteTransferThreshold )
   {
-    QString thisStr;
-    thisStr.sprintf( "%p", this );
+    const QString thisStr = QStringLiteral( "%1" ).arg( reinterpret_cast< quintptr >( this ), QT_POINTER_SIZE * 2, 16, QLatin1Char( '0' ) );
     ++ mCounter;
     mWriterFilename = QDir( mShared->acquireCacheDirectory() ).filePath( QStringLiteral( "iterator_%1_%2.bin" ).arg( thisStr ).arg( mCounter ) );
     QgsDebugMsgLevel( QStringLiteral( "Transferring feature iterator cache to %1" ).arg( mWriterFilename ), 4 );
diff --git a/src/providers/wfs/qgsbackgroundcachedshareddata.cpp b/src/providers/wfs/qgsbackgroundcachedshareddata.cpp
index 929b5ce35363..2e329777205e 100644
--- a/src/providers/wfs/qgsbackgroundcachedshareddata.cpp
+++ b/src/providers/wfs/qgsbackgroundcachedshareddata.cpp
@@ -212,8 +212,7 @@ bool QgsBackgroundCachedSharedData::createCache()
     logMessageWithReason( QStringLiteral( "GDAL SQLite driver not available" ) );
     return false;
   }
-  QString vsimemFilename;
-  vsimemFilename.sprintf( "/vsimem/qgis_cache_template_%p/features.sqlite", this );
+  const QString vsimemFilename = QStringLiteral( "/vsimem/qgis_cache_template_%1/features.sqlite" ).arg( reinterpret_cast< quintptr >( this ), QT_POINTER_SIZE * 2, 16, QLatin1Char( '0' ) );
   mCacheTablename = CPLGetBasename( vsimemFilename.toStdString().c_str() );
   VSIUnlink( vsimemFilename.toStdString().c_str() );
   const char *apszOptions[] = { "INIT_WITH_EPSG=NO", "SPATIALITE=YES", nullptr };
diff --git a/src/providers/wfs/qgsoapifitemsrequest.cpp b/src/providers/wfs/qgsoapifitemsrequest.cpp
index 3645f5710dde..52e91fbf7fdb 100644
--- a/src/providers/wfs/qgsoapifitemsrequest.cpp
+++ b/src/providers/wfs/qgsoapifitemsrequest.cpp
@@ -84,8 +84,7 @@ void QgsOapifItemsRequest::processReply()
     return;
   }
 
-  QString vsimemFilename;
-  vsimemFilename.sprintf( "/vsimem/oaipf_%p.json", &buffer );
+  const QString vsimemFilename = QStringLiteral( "/vsimem/oaipf_%1.json" ).arg( reinterpret_cast< quintptr >( &buffer ), QT_POINTER_SIZE * 2, 16, QLatin1Char( '0' ) );
   VSIFCloseL( VSIFileFromMemBuffer( vsimemFilename.toUtf8().constData(),
                                     const_cast<GByte *>( reinterpret_cast<const GByte *>( buffer.constData() ) ),
                                     buffer.size(),
diff --git a/src/providers/wfs/qgswfsprovider.cpp b/src/providers/wfs/qgswfsprovider.cpp
index a99f11ce212a..29195e5d4961 100644
--- a/src/providers/wfs/qgswfsprovider.cpp
+++ b/src/providers/wfs/qgswfsprovider.cpp
@@ -1078,9 +1078,7 @@ QString QgsWFSProvider::convertToXML( const QVariant &value )
     QDateTime dt = value.toDateTime().toUTC();
     if ( !dt.isNull() )
     {
-      valueStr.sprintf( "%04d-%02d-%02dT%02d:%02d:%02d.%03dZ",
-                        dt.date().year(), dt.date().month(), dt.date().day(),
-                        dt.time().hour(), dt.time().minute(), dt.time().second(), dt.time().msec() );
+      valueStr = dt.toString( QStringLiteral( "yyyy-MM-ddThh:mm:ss.zzzZ" ) );
     }
     else
     {
diff --git a/src/providers/wfs/qgswfssourceselect.cpp b/src/providers/wfs/qgswfssourceselect.cpp
index 7f78024c804f..6fb524fbd2a0 100644
--- a/src/providers/wfs/qgswfssourceselect.cpp
+++ b/src/providers/wfs/qgswfssourceselect.cpp
@@ -837,7 +837,7 @@ void QgsWFSSourceSelect::changeCRSFilter()
     QMap<QString, QStringList >::const_iterator crsIterator = mAvailableCRS.constFind( currentTypename );
     if ( crsIterator != mAvailableCRS.constEnd() )
     {
-      QSet<QString> crsNames( crsIterator->toSet() );
+      QSet<QString> crsNames( qgis::listToSet( *crsIterator ) );
 
       if ( mProjectionSelector )
       {
diff --git a/src/providers/wms/qgswmsprovider.cpp b/src/providers/wms/qgswmsprovider.cpp
index fab4c2c3804d..dfd8834d203c 100644
--- a/src/providers/wms/qgswmsprovider.cpp
+++ b/src/providers/wms/qgswmsprovider.cpp
@@ -581,7 +581,7 @@ void QgsWmsProvider::fetchOtherResTiles( QgsTileMode tileMode, const QgsRectangl
   }
 
   // get URLs of tiles because their URLs are used as keys in the tile cache
-  TilePositions tiles = tilesSet.toList();
+  TilePositions tiles = qgis::setToList( tilesSet );
   TileRequests requests;
   switch ( tileMode )
   {
@@ -3296,7 +3296,7 @@ QgsRasterIdentifyResult QgsWmsProvider::identify( const QgsPointXY &point, QgsRa
           QgsDebugMsg( "parsing GML error: " + err.message() );
           return QgsRasterIdentifyResult( err );
         }
-        results.insert( results.size(), qVariantFromValue( featureStoreList ) );
+        results.insert( results.size(), QVariant::fromValue( featureStoreList ) );
       }
       else if ( jsonPart != -1 )
       {
@@ -3423,7 +3423,7 @@ QgsRasterIdentifyResult QgsWmsProvider::identify( const QgsPointXY &point, QgsRa
           results.insert( results.size(), err );  // string returned for format type "feature" means error
         }
 
-        results.insert( results.size(), qVariantFromValue( featureStoreList ) );
+        results.insert( results.size(), QVariant::fromValue( featureStoreList ) );
       }
     }
   }
diff --git a/src/providers/wms/qgswmssourceselect.cpp b/src/providers/wms/qgswmssourceselect.cpp
index 81bcc4f0d7f5..99118d359beb 100644
--- a/src/providers/wms/qgswmssourceselect.cpp
+++ b/src/providers/wms/qgswmssourceselect.cpp
@@ -786,9 +786,9 @@ void QgsWMSSourceSelect::collectNamedLayers( QTreeWidgetItem *item, QStringList
     titles << titleName;
 
     if ( mCRSs.isEmpty() )
-      mCRSs = item->data( 0, Qt::UserRole + 2 ).toStringList().toSet();
+      mCRSs = qgis::listToSet( item->data( 0, Qt::UserRole + 2 ).toStringList() );
     else
-      mCRSs.intersect( item->data( 0, Qt::UserRole + 2 ).toStringList().toSet() );
+      mCRSs.intersect( qgis::listToSet( item->data( 0, Qt::UserRole + 2 ).toStringList() ) );
   }
 }
 
@@ -832,9 +832,9 @@ void QgsWMSSourceSelect::lstLayers_itemSelectionChanged()
       styles << QString();
       titles << titleName;
       if ( mCRSs.isEmpty() )
-        mCRSs = item->data( 0, Qt::UserRole + 2 ).toStringList().toSet();
+        mCRSs = qgis::listToSet( item->data( 0, Qt::UserRole + 2 ).toStringList() );
       else
-        mCRSs.intersect( item->data( 0, Qt::UserRole + 2 ).toStringList().toSet() );
+        mCRSs.intersect( qgis::listToSet( item->data( 0, Qt::UserRole + 2 ).toStringList() ) );
     }
     else
     {
@@ -843,9 +843,9 @@ void QgsWMSSourceSelect::lstLayers_itemSelectionChanged()
       styles << styleName;
       titles << titleName;
       if ( mCRSs.isEmpty() )
-        mCRSs = item->parent()->data( 0, Qt::UserRole + 2 ).toStringList().toSet();
+        mCRSs = qgis::listToSet( item->parent()->data( 0, Qt::UserRole + 2 ).toStringList() );
       else
-        mCRSs.intersect( item->parent()->data( 0, Qt::UserRole + 2 ).toStringList().toSet() );
+        mCRSs.intersect( qgis::listToSet( item->parent()->data( 0, Qt::UserRole + 2 ).toStringList() ) );
     }
   }
 
@@ -1149,13 +1149,13 @@ void QgsWMSSourceSelect::filterLayers( const QString &searchText )
     // hide all
     setChildrenVisible( lstLayers->invisibleRootItem(), false );
     // find and show matching items in name and title columns
-    QSet<QTreeWidgetItem *> items = lstLayers->findItems( searchText, Qt::MatchContains | Qt::MatchRecursive, 1 ).toSet();
-    items.unite( lstLayers->findItems( searchText, Qt::MatchContains | Qt::MatchRecursive, 2 ).toSet() );
+    QSet<QTreeWidgetItem *> items = qgis::listToSet( lstLayers->findItems( searchText, Qt::MatchContains | Qt::MatchRecursive, 1 ) );
+    items.unite( qgis::listToSet( lstLayers->findItems( searchText, Qt::MatchContains | Qt::MatchRecursive, 2 ) ) );
 
     // if nothing found, search in abstract too
     if ( items.isEmpty() )
     {
-      items = lstLayers->findItems( searchText, Qt::MatchContains | Qt::MatchRecursive, 3 ).toSet();
+      items = qgis::listToSet( lstLayers->findItems( searchText, Qt::MatchContains | Qt::MatchRecursive, 3 ) );
     }
 
     mTreeInitialExpand.clear();
diff --git a/src/server/services/wms/qgswmsgetcapabilities.cpp b/src/server/services/wms/qgswmsgetcapabilities.cpp
index d3ab7d09894e..81f40185afc7 100644
--- a/src/server/services/wms/qgswmsgetcapabilities.cpp
+++ b/src/server/services/wms/qgswmsgetcapabilities.cpp
@@ -1258,7 +1258,7 @@ namespace QgsWms
                 uniqueValues.unite( vl->uniqueValues( endFieldIndex ) );
               }
               // sort unique values
-              QList<QVariant> values = uniqueValues.toList();
+              QList<QVariant> values = qgis::setToList( uniqueValues );
               std::sort( values.begin(), values.end() );
 
               QDomElement dimElem = doc.createElement( QStringLiteral( "Dimension" ) );
@@ -1771,7 +1771,7 @@ namespace QgsWms
       }
 
       QStringList outputCrsList = QgsServerProjectUtils::wmsOutputCrsList( *project );
-      appendCrsElementsToLayer( doc, groupElem, combinedCRSSet.toList(), outputCrsList );
+      appendCrsElementsToLayer( doc, groupElem, qgis::setToList( combinedCRSSet ), outputCrsList );
 
       QgsCoordinateReferenceSystem groupCRS = project->crs();
       if ( considerMapExtent )
@@ -1782,7 +1782,7 @@ namespace QgsWms
           combinedBBox = mapRect;
         }
       }
-      appendLayerBoundingBoxes( doc, groupElem, combinedBBox, groupCRS, combinedCRSSet.toList(), outputCrsList, project );
+      appendLayerBoundingBoxes( doc, groupElem, combinedBBox, groupCRS, qgis::setToList( combinedCRSSet ), outputCrsList, project );
 
     }
 
diff --git a/src/server/services/wms/qgswmsrenderer.cpp b/src/server/services/wms/qgswmsrenderer.cpp
index d3b52aeffac5..dca06759e412 100644
--- a/src/server/services/wms/qgswmsrenderer.cpp
+++ b/src/server/services/wms/qgswmsrenderer.cpp
@@ -2885,7 +2885,7 @@ namespace QgsWms
             uniqueValues.unite( layer->uniqueValues( endFieldIndex ) );
           }
           // sort unique values
-          QList<QVariant> values = uniqueValues.toList();
+          QList<QVariant> values = qgis::setToList( uniqueValues );
           std::sort( values.begin(), values.end() );
           if ( dim.defaultDisplayType == QgsVectorLayerServerProperties::WmsDimensionInfo::MinValue )
           {
diff --git a/tests/bench/qgsbench.h b/tests/bench/qgsbench.h
index 357055ea3eea..ed4d29856b1b 100644
--- a/tests/bench/qgsbench.h
+++ b/tests/bench/qgsbench.h
@@ -83,7 +83,7 @@ class QgsBench :  public QObject
 
     double mUserStart;
     double mSysStart;
-    QTime mWallTime; // 'wall clock' time
+    QElapsedTimer mWallTime; // 'wall clock' time
 
     // user, sys, total times
     QVector<double *> mTimes;
diff --git a/tests/src/analysis/testqgsprocessing.cpp b/tests/src/analysis/testqgsprocessing.cpp
index 2584d55665ff..99e45110da9d 100644
--- a/tests/src/analysis/testqgsprocessing.cpp
+++ b/tests/src/analysis/testqgsprocessing.cpp
@@ -691,20 +691,20 @@ void TestQgsProcessing::addProvider()
   //try adding another provider
   DummyProvider *p2 = new DummyProvider( "p2" );
   QVERIFY( r.addProvider( p2 ) );
-  QCOMPARE( r.providers().toSet(), QSet< QgsProcessingProvider * >() << p << p2 );
+  QCOMPARE( qgis::listToSet( r.providers() ), QSet< QgsProcessingProvider * >() << p << p2 );
   QCOMPARE( spyProviderAdded.count(), 2 );
   QCOMPARE( spyProviderAdded.last().at( 0 ).toString(), QString( "p2" ) );
 
   //try adding a provider with duplicate id
   DummyProvider *p3 = new DummyProvider( "p2" );
   QVERIFY( !r.addProvider( p3 ) );
-  QCOMPARE( r.providers().toSet(), QSet< QgsProcessingProvider * >() << p << p2 );
+  QCOMPARE( qgis::listToSet( r.providers() ), QSet< QgsProcessingProvider * >() << p << p2 );
   QCOMPARE( spyProviderAdded.count(), 2 );
 
   // test that adding a provider which does not load means it is not added to registry
   DummyProviderNoLoad *p4 = new DummyProviderNoLoad( "p4" );
   QVERIFY( !r.addProvider( p4 ) );
-  QCOMPARE( r.providers().toSet(), QSet< QgsProcessingProvider * >() << p << p2 );
+  QCOMPARE( qgis::listToSet( r.providers() ), QSet< QgsProcessingProvider * >() << p << p2 );
   QCOMPARE( spyProviderAdded.count(), 2 );
 }
 
diff --git a/tests/src/app/testqgsmaptooladdfeatureline.cpp b/tests/src/app/testqgsmaptooladdfeatureline.cpp
index b744fb1422b0..d83459e7443a 100644
--- a/tests/src/app/testqgsmaptooladdfeatureline.cpp
+++ b/tests/src/app/testqgsmaptooladdfeatureline.cpp
@@ -561,7 +561,7 @@ void TestQgsMapToolAddFeatureLine::testTopologicalEditingZ()
   QString wkt = "LineStringZ (6 6.5 5, 6.25 6.5 333, 6.75 6.5 333, 7.25 6.5 333, 7.5 6.5 333)";
   QCOMPARE( mLayerTopoZ->getFeature( newFid ).geometry(), QgsGeometry::fromWkt( wkt ) );
   wkt = "MultiLineStringZ ((7.25 6 0, 7.25 6.5 333, 7.25 7 0, 7.5 7 0, 7.5 6.5 333, 7.5 6 0, 7.25 6 0),(6 6 0, 6 6.5 5, 6 7 10, 7 7 0, 7 6 0, 6 6 0),(6.25 6.25 0, 6.75 6.25 0, 6.75 6.5 333, 6.75 6.75 0, 6.25 6.75 0, 6.25 6.5 333, 6.25 6.25 0))";
-  QCOMPARE( mLayerTopoZ->getFeature( oldFids.toList().last() ).geometry(), QgsGeometry::fromWkt( wkt ) );
+  QCOMPARE( mLayerTopoZ->getFeature( qgis::setToList( oldFids ).last() ).geometry(), QgsGeometry::fromWkt( wkt ) );
 
   mLayerLine->undoStack()->undo();
 
diff --git a/tests/src/core/testqgsexpressioncontext.cpp b/tests/src/core/testqgsexpressioncontext.cpp
index e08fe92645ef..097bf161da76 100644
--- a/tests/src/core/testqgsexpressioncontext.cpp
+++ b/tests/src/core/testqgsexpressioncontext.cpp
@@ -939,7 +939,7 @@ void TestQgsExpressionContext::readWriteScope()
   // valid element
   s2.readXml( e, QgsReadWriteContext() );
   QCOMPARE( s2.variableCount(), 2 );
-  QCOMPARE( s2.variableNames().toSet(), QSet< QString >() << QStringLiteral( "v1" ) << QStringLiteral( "v2" ) );
+  QCOMPARE( qgis::listToSet( s2.variableNames() ), QSet< QString >() << QStringLiteral( "v1" ) << QStringLiteral( "v2" ) );
   QCOMPARE( s2.variable( QStringLiteral( "v1" ) ).toString(), QStringLiteral( "t1" ) );
   QCOMPARE( s2.variable( QStringLiteral( "v2" ) ).toInt(), 55 );
 }
diff --git a/tests/src/core/testqgslabelingengine.cpp b/tests/src/core/testqgslabelingengine.cpp
index b41020258b94..514590fc5ab4 100644
--- a/tests/src/core/testqgslabelingengine.cpp
+++ b/tests/src/core/testqgslabelingengine.cpp
@@ -752,7 +752,7 @@ void TestQgsLabelingEngine::testParticipatingLayers()
   QgsPalLayerSettings settings2;
   QgsVectorLayerLabelProvider *provider2 = new QgsVectorLayerLabelProvider( layer2, QStringLiteral( "test2" ), true, &settings2 );
   engine.addProvider( provider2 );
-  QCOMPARE( engine.participatingLayers().toSet(), QSet< QgsMapLayer * >() << vl << layer2 );
+  QCOMPARE( qgis::listToSet( engine.participatingLayers() ), QSet< QgsMapLayer * >() << vl << layer2 );
 
   // add a rule-based labeling node
   QgsRuleBasedLabeling::Rule *root = new QgsRuleBasedLabeling::Rule( nullptr );
@@ -764,7 +764,7 @@ void TestQgsLabelingEngine::testParticipatingLayers()
   QgsVectorLayer *layer3 = new QgsVectorLayer( QStringLiteral( "Point?field=col1:integer" ), QStringLiteral( "layer3" ), QStringLiteral( "memory" ) );
   QgsRuleBasedLabelProvider *ruleProvider = new QgsRuleBasedLabelProvider( QgsRuleBasedLabeling( root ), layer3 );
   engine.addProvider( ruleProvider );
-  QCOMPARE( engine.participatingLayers().toSet(), QSet< QgsMapLayer * >() << vl << layer2 << layer3 );
+  QCOMPARE( qgis::listToSet( engine.participatingLayers() ), QSet< QgsMapLayer * >() << vl << layer2 << layer3 );
 }
 
 bool TestQgsLabelingEngine::imageCheck( const QString &testName, QImage &image, int mismatchCount )
diff --git a/tests/src/core/testqgslayoutmap.cpp b/tests/src/core/testqgslayoutmap.cpp
index ce126a4f090a..aa7e3abbeb3f 100644
--- a/tests/src/core/testqgslayoutmap.cpp
+++ b/tests/src/core/testqgslayoutmap.cpp
@@ -424,32 +424,32 @@ void TestQgsLayoutMap::dataDefinedStyles()
   // test following of preset
   map->setFollowVisibilityPreset( true );
   map->setFollowVisibilityPresetName( QStringLiteral( "test preset" ) );
-  QSet<QgsMapLayer *> result = map->layersToRender().toSet();
+  QSet<QgsMapLayer *> result = qgis::listToSet( map->layersToRender() );
   QCOMPARE( result.count(), 2 );
   map->setFollowVisibilityPresetName( QString() );
 
   //test malformed style string
   map->dataDefinedProperties().setProperty( QgsLayoutObject::MapStylePreset, QgsProperty::fromExpression( QStringLiteral( "5" ) ) );
-  result = map->layersToRender().toSet();
-  QCOMPARE( result, layers.toSet() );
+  result = qgis::listToSet( map->layersToRender() );
+  QCOMPARE( result, qgis::listToSet( layers ) );
 
   //test valid preset
   map->dataDefinedProperties().setProperty( QgsLayoutObject::MapStylePreset, QgsProperty::fromExpression( QStringLiteral( "'test preset'" ) ) );
-  result = map->layersToRender().toSet();
+  result = qgis::listToSet( map->layersToRender() );
   QCOMPARE( result.count(), 2 );
   QVERIFY( result.contains( mLinesLayer ) );
   QVERIFY( result.contains( mPointsLayer ) );
 
   //test non-existent preset
   map->dataDefinedProperties().setProperty( QgsLayoutObject::MapStylePreset, QgsProperty::fromExpression( QStringLiteral( "'bad preset'" ) ) );
-  result = map->layersToRender().toSet();
-  QCOMPARE( result, layers.toSet() );
+  result = qgis::listToSet( map->layersToRender() );
+  QCOMPARE( result, qgis::listToSet( layers ) );
 
   //test that dd layer set overrides style layers
   map->dataDefinedProperties().setProperty( QgsLayoutObject::MapStylePreset, QgsProperty::fromExpression( QStringLiteral( "'test preset'" ) ) );
   map->dataDefinedProperties().setProperty( QgsLayoutObject::MapLayers, QgsProperty::fromExpression(
         QStringLiteral( "'%1'" ).arg( mPolysLayer->name() ) ) );
-  result = map->layersToRender().toSet();
+  result = qgis::listToSet( map->layersToRender() );
   QCOMPARE( result.count(), 1 );
   QVERIFY( result.contains( mPolysLayer ) );
   map->dataDefinedProperties().setProperty( QgsLayoutObject::MapLayers, QgsProperty() );
diff --git a/tests/src/core/testqgsspatialindex.cpp b/tests/src/core/testqgsspatialindex.cpp
index c359964d9450..5b23a463bf40 100644
--- a/tests/src/core/testqgsspatialindex.cpp
+++ b/tests/src/core/testqgsspatialindex.cpp
@@ -24,6 +24,7 @@
 #include <qgsvectordataprovider.h>
 #include <qgsvectorlayer.h>
 #include "qgslinestring.h"
+#include "qgslogger.h"
 
 static QgsFeature _pointFeature( QgsFeatureId id, qreal x, qreal y )
 {
@@ -188,7 +189,7 @@ class TestQgsSpatialIndex : public QObject
         vl->dataProvider()->addFeatures( flist );
       }
 
-      QTime t;
+      QElapsedTimer t;
       QgsSpatialIndex *indexBulk = nullptr;
       QgsSpatialIndex *indexInsert = nullptr;
 
@@ -199,14 +200,14 @@ class TestQgsSpatialIndex : public QObject
         while ( fi.nextFeature( f ) )
           ;
       }
-      qDebug( "iter only: %d ms", t.elapsed() );
+      QgsDebugMsg( QStringLiteral( "iter only: %1 ms" ).arg( t.elapsed() ) );
 
       t.start();
       {
         QgsFeatureIterator fi = vl->getFeatures();
         indexBulk = new QgsSpatialIndex( fi );
       }
-      qDebug( "bulk load: %d ms", t.elapsed() );
+      QgsDebugMsg( QStringLiteral( "bulk load: %1 ms" ).arg( t.elapsed() ) );
 
       t.start();
       {
@@ -216,7 +217,7 @@ class TestQgsSpatialIndex : public QObject
         while ( fi.nextFeature( f ) )
           indexInsert->addFeature( f );
       }
-      qDebug( "insert:    %d ms", t.elapsed() );
+      QgsDebugMsg( QStringLiteral( "insert:    %1 ms" ).arg( t.elapsed() ) );
 
       // test whether a query will give us the same results
       QgsRectangle rect( 4.9, 4.9, 5.1, 5.1 );
diff --git a/tests/src/core/testqgstaskmanager.cpp b/tests/src/core/testqgstaskmanager.cpp
index 304549a75f0e..a66ce1aa4bf6 100644
--- a/tests/src/core/testqgstaskmanager.cpp
+++ b/tests/src/core/testqgstaskmanager.cpp
@@ -1215,7 +1215,7 @@ void TestQgsTaskManager::activeTasks()
     QCoreApplication::processEvents();
   }
   flushEvents();
-  QCOMPARE( manager.activeTasks().toSet(), ( QList< QgsTask * >() << task ).toSet() );
+  QCOMPARE( qgis::listToSet( manager.activeTasks() ), qgis::listToSet( QList< QgsTask * >() << task ) );
   QCOMPARE( manager.countActiveTasks(), 1 );
   QCOMPARE( spy.count(), 1 );
   QCOMPARE( spy.last().at( 0 ).toInt(), 1 );
@@ -1225,7 +1225,7 @@ void TestQgsTaskManager::activeTasks()
     QCoreApplication::processEvents();
   }
   flushEvents();
-  QCOMPARE( manager.activeTasks().toSet(), ( QList< QgsTask * >() << task << task2 ).toSet() );
+  QCOMPARE( qgis::listToSet( manager.activeTasks() ), qgis::listToSet( QList< QgsTask * >() << task << task2 ) );
   QCOMPARE( manager.countActiveTasks(), 2 );
   QCOMPARE( spy.count(), 2 );
   QCOMPARE( spy.last().at( 0 ).toInt(), 2 );
@@ -1235,7 +1235,7 @@ void TestQgsTaskManager::activeTasks()
     QCoreApplication::processEvents();
   }
   flushEvents();
-  QCOMPARE( manager.activeTasks().toSet(), ( QList< QgsTask * >() << task2 ).toSet() );
+  QCOMPARE( qgis::listToSet( manager.activeTasks() ), qgis::listToSet( QList< QgsTask * >() << task2 ) );
   QCOMPARE( manager.countActiveTasks(), 1 );
   QCOMPARE( spy.count(), 3 );
   QCOMPARE( spy.last().at( 0 ).toInt(), 1 );
diff --git a/tests/src/core/testziplayer.cpp b/tests/src/core/testziplayer.cpp
index 70c72477a090..de54b027faa5 100644
--- a/tests/src/core/testziplayer.cpp
+++ b/tests/src/core/testziplayer.cpp
@@ -155,7 +155,7 @@ bool TestZipLayer::testZipItem( const QString &myFileName, const QString &myChil
   QgsZipItem *myZipItem = new QgsZipItem( nullptr, myFileInfo.fileName(), myFileName );
   myZipItem->populate();
   // wait until populated in separate thread
-  QTime time;
+  QElapsedTimer time;
   time.start();
   while ( myZipItem->state() != QgsDataItem::Populated && time.elapsed() < 5000 )
   {
diff --git a/tests/src/gui/testqgsdualview.cpp b/tests/src/gui/testqgsdualview.cpp
index 05904af97e94..8a1555aaca12 100644
--- a/tests/src/gui/testqgsdualview.cpp
+++ b/tests/src/gui/testqgsdualview.cpp
@@ -143,7 +143,7 @@ void TestQgsDualView::testFilterSelected()
   // select some features
   QList< QgsFeatureId > selected;
   selected << ids.at( 1 ) << ids.at( 3 );
-  mPointsLayer->selectByIds( selected.toSet() );
+  mPointsLayer->selectByIds( qgis::listToSet( selected ) );
 
   mDualView->setFilterMode( QgsAttributeTableFilterModel::ShowSelected );
   QCOMPARE( mDualView->tableView()->model()->rowCount(), 2 );
diff --git a/tests/src/providers/testqgswcspublicservers.cpp b/tests/src/providers/testqgswcspublicservers.cpp
index d5b552c30055..6defd4fc02be 100644
--- a/tests/src/providers/testqgswcspublicservers.cpp
+++ b/tests/src/providers/testqgswcspublicservers.cpp
@@ -404,7 +404,7 @@ void TestQgsWcsPublicServers::test()
 
         Q_FOREACH ( const QString &provider, providers )
         {
-          QTime time;
+          QElapsedTimer time;
           time.start();
           QString uri;
           if ( provider == QLatin1String( "wcs" ) )