Undo stack pop-up in 8.4.0

[Tom Cunningham]

> Did you run the Qt5 or the Qt6 version of digiKam ?

I was running the Qt6 version. When I tried the Qt5 version, all that I got was a white window, with "digiKam" in the upper left corner. When I clicked the "X" in the upper right corner to exit, and attempted to reinstall the Qt6 version, the installer of course wanted to uninstall the Qt5 version. However, the uninstall balked, because it claimed digiKam was still running, although I saw nothing in the Task Manaager. I just clicked on "Continue", the uninstall completed, but when it tried to do the reinstall it again complained about digiKam still running. I had to reboot to get around this. The Qt6 version installs and runs fine (other than the undo stack issue).

> Did you enable the versioning feature in the Image Editor ?

Versioning is not enabled in the Image Editor.