Add comments to unlcear translatable strings

Author: borysiasty

src/app/qgisapp.cpp

@@ -1206,7 +1206,7 @@ QgisApp::QgisApp( QSplashScreen *splash, bool restorePlugins, bool skipVersionCh
   zoomInToolShortCut->setWhatsThis( tr( "Zoom in (secondary)" ) );
   zoomInToolShortCut->setProperty( "Icon", QgsApplication::getThemeIcon( QStringLiteral( "/mActionZoomIn.svg" ) ) );
 
-  QShortcut *toggleSnapping = new QShortcut( QKeySequence( tr( "S" ) ), this );
+  QShortcut *toggleSnapping = new QShortcut( QKeySequence( tr( "S", "Keyboard Shortcut: Toggle snapping" ) ), this );
   toggleSnapping->setObjectName( QStringLiteral( "toggleSnapping" ) );
   toggleSnapping->setWhatsThis( tr( "Toggle snapping" ) );
   toggleSnapping->setProperty( "Icon", QgsApplication::getThemeIcon( QStringLiteral( "/mIconSnapping.svg" ) ) );

src/app/qgssnappingwidget.cpp

@@ -147,7 +147,7 @@ QgsSnappingWidget::QgsSnappingWidget( QgsProject *project, QgsMapCanvas *canvas,
   mEnableTracingAction->setCheckable( true );
   mEnableTracingAction->setIcon( QIcon( QgsApplication::getThemeIcon( "/mActionTracing.svg" ) ) );
   mEnableTracingAction->setToolTip( tr( "Enable Tracing (T)" ) );
-  mEnableTracingAction->setShortcut( tr( "T", "Enable Tracing" ) );
+  mEnableTracingAction->setShortcut( tr( "T", "Keyboard shortcut: Enable tracing" ) );
   mEnableTracingAction->setObjectName( QStringLiteral( "EnableTracingAction" ) );
 
   mTracingOffsetSpinBox = new QgsDoubleSpinBox;