Unsolved QtCreator: Frequently appearing info dialogs cause crashes

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Hello,

a few days ago, the Qt Creator (version 4.15.0; Windows 10) started showing a dialog like the one seen below (the process id is different every time) about five times per minute when editing a QML file in Design mode. About one in twenty dialogs made the IDE freeze and crash after a few seconds. There were never shown more than 30 dialogs per Creator instance.

Does anyone have an idea about what could cause this strange behaviour?