When adding a lot of tabs hosting a QQuickWidget then it can run out of resources depending on the system. This happens even if QQuickWindow::setSceneGraphPersistent(false) and QQuickWindow::setPersistentOpenGLContext(false) is used on the window inside the QQuickWidget. Therefore it indicates that there is something not being cleaned up correctly.

Steps to reproduce:

• Launch app
• Add a few tabs
• After approx 7 tabs, crashes start to show (CreateDIBSection fails, failures to launch threads)
• If it has not crashed yet: maximize the window

With MinGW 7.3/32bit (debug):

qrc:/main.qml:2:1: plugin cannot be loaded for module "QtQuick.Controls": Cannot load library . ..\qml\QtQuick\Controls.2\qtquickcontrols2plugind.dll: Not enough memory resources are available to process this command.