There is no ability to move source files between directories in the project tree, so I renamed a header file with new directory prefix. There was a dialog which asked if I would like to reanme a .cpp file too, I answered 'yes'.

As the result Qt Creator got stuck, but in file manager I can see that new directory was created and my header file was moved inside, but .cpp file was left unchanged.

Also I noticed a temporary CmakeLists file being recreated again and again (see 2024-05-18 17-20-29.mkv) until Qt Creator process was killed