I would appreciate any help to find the cause of this weird issue.

I am on Fedora Silverblue latest.

From time to time after the computer has been running a while in QtCreator,

the main thread of projects is suddenly called multiple times.

right after the QGuiApplication app;  I have a qDebug() << "main thread called";

running it via qtcreator presents "main thread called" up to 7 times.

After reboot this issue is gone. 

In one project I am using 

SortFilterProxyModel (include(SortFilterProxyModel/SortFilterProxyModel.pri) 

I mention this because https://github.com/oKcerG/SortFilterProxyModel/ 

parses a warning in general messages 

Project WARNING: SortFilterProxyModel needs at least c++11, add CONFIG += c++11 to your .pro

if you don't have that in your .pro file. 

When the issue appears this warning is parsed as well multiple times.

Closing qtcreator has no effect only reboot has.