diff --git a/external/o2/src/o2.cpp b/external/o2/src/o2.cpp
index 0b11b60a0811..f5939587d5dd 100644
--- a/external/o2/src/o2.cpp
+++ b/external/o2/src/o2.cpp
@@ -219,7 +219,7 @@ void O2::link() {
         QUrl url(tokenUrl_);
         QNetworkRequest tokenRequest(url);
         tokenRequest.setHeader(QNetworkRequest::ContentTypeHeader, "application/x-www-form-urlencoded");
-        QNetworkReply *tokenReply = manager_->post(tokenRequest, payload);
+        QNetworkReply *tokenReply = getManager()->post(tokenRequest, payload);
 
         connect(tokenReply, SIGNAL(finished()), this, SLOT(onTokenReplyFinished()), Qt::QueuedConnection);
         connect(tokenReply, SIGNAL(error(QNetworkReply::NetworkError)), this, SLOT(onTokenReplyError(QNetworkReply::NetworkError)), Qt::QueuedConnection);
@@ -268,7 +268,7 @@ void O2::onVerificationReceived(const QMap<QString, QString> response) {
 
         qDebug() << QString("O2::onVerificationReceived: Exchange access code data:\n%1").arg(QString(data));
 
-        QNetworkReply *tokenReply = manager_->post(tokenRequest, data);
+        QNetworkReply *tokenReply = getManager()->post(tokenRequest, data);
         timedReplies_.add(tokenReply);
         connect(tokenReply, SIGNAL(finished()), this, SLOT(onTokenReplyFinished()), Qt::QueuedConnection);
         connect(tokenReply, SIGNAL(error(QNetworkReply::NetworkError)), this, SLOT(onTokenReplyError(QNetworkReply::NetworkError)), Qt::QueuedConnection);
@@ -390,6 +390,11 @@ void O2::setExpires(int v) {
     store_->setValue(key, QString::number(v));
 }
 
+QNetworkAccessManager *O2::getManager()
+{
+    return manager_;
+}
+
 QString O2::refreshToken() {
     QString key = QString(O2_KEY_REFRESH_TOKEN).arg(clientId_);
     return store_->value(key);
@@ -424,7 +429,7 @@ void O2::refresh() {
     parameters.insert(O2_OAUTH2_GRANT_TYPE, O2_OAUTH2_REFRESH_TOKEN);
 
     QByteArray data = buildRequestBody(parameters);
-    QNetworkReply *refreshReply = manager_->post(refreshRequest, data);
+    QNetworkReply *refreshReply = getManager()->post(refreshRequest, data);
     timedReplies_.add(refreshReply);
     connect(refreshReply, SIGNAL(finished()), this, SLOT(onRefreshFinished()), Qt::QueuedConnection);
     connect(refreshReply, SIGNAL(error(QNetworkReply::NetworkError)), this, SLOT(onRefreshError(QNetworkReply::NetworkError)), Qt::QueuedConnection);
diff --git a/external/o2/src/o2.h b/external/o2/src/o2.h
index c350e1506cad..c09eab592806 100644
--- a/external/o2/src/o2.h
+++ b/external/o2/src/o2.h
@@ -161,6 +161,8 @@ protected Q_SLOTS:
     /// Set token expiration time.
     void setExpires(int v);
 
+    virtual QNetworkAccessManager *getManager();
+
 protected:
     QString username_;
     QString password_;
diff --git a/src/auth/oauth2/qgso2.cpp b/src/auth/oauth2/qgso2.cpp
index 2b2fde4dd2bc..d4ce2a18f4e2 100644
--- a/src/auth/oauth2/qgso2.cpp
+++ b/src/auth/oauth2/qgso2.cpp
@@ -231,7 +231,7 @@ void QgsO2::link()
     QUrl url( tokenUrl_ );
     QNetworkRequest tokenRequest( url );
     tokenRequest.setHeader( QNetworkRequest::ContentTypeHeader, QLatin1Literal( "application/x-www-form-urlencoded" ) );
-    QNetworkReply *tokenReply = manager_->post( tokenRequest, payload );
+    QNetworkReply *tokenReply = getManager()->post( tokenRequest, payload );
 
     connect( tokenReply, SIGNAL( finished() ), this, SLOT( onTokenReplyFinished() ), Qt::QueuedConnection );
     connect( tokenReply, SIGNAL( error( QNetworkReply::NetworkError ) ), this, SLOT( onTokenReplyError( QNetworkReply::NetworkError ) ), Qt::QueuedConnection );
@@ -299,7 +299,7 @@ void QgsO2::onVerificationReceived( QMap<QString, QString> response )
     parameters.insert( O2_OAUTH2_REDIRECT_URI, redirectUri_ );
     parameters.insert( O2_OAUTH2_GRANT_TYPE, O2_AUTHORIZATION_CODE );
     QByteArray data = buildRequestBody( parameters );
-    QNetworkReply *tokenReply = manager_->post( tokenRequest, data );
+    QNetworkReply *tokenReply = getManager()->post( tokenRequest, data );
     timedReplies_.add( tokenReply );
     connect( tokenReply, &QNetworkReply::finished, this, &QgsO2::onTokenReplyFinished, Qt::QueuedConnection );
     connect( tokenReply, qgis::overload<QNetworkReply::NetworkError>::of( &QNetworkReply::error ), this, &QgsO2::onTokenReplyError, Qt::QueuedConnection );
@@ -336,3 +336,8 @@ void QgsO2::onVerificationReceived( QMap<QString, QString> response )
     setRefreshToken( response.value( O2_OAUTH2_REFRESH_TOKEN ) );
   }
 }
+
+QNetworkAccessManager *QgsO2::getManager()
+{
+  return QgsNetworkAccessManager::instance();
+}
diff --git a/src/auth/oauth2/qgso2.h b/src/auth/oauth2/qgso2.h
index 683bb0441922..834dcce7529f 100644
--- a/src/auth/oauth2/qgso2.h
+++ b/src/auth/oauth2/qgso2.h
@@ -74,6 +74,10 @@ class QgsO2: public O2
     //! Handle verification response.
     void onVerificationReceived( QMap<QString, QString> response ) override;
 
+  protected:
+
+    QNetworkAccessManager* getManager() override;
+
   signals:
 
     //! Emitted when the state has changed