error message during restart and changing theme see attachment

I was using quick design editor, when I tried to change the theme.
the purple and blue colors for the current directory in the file system panel
was unreadable.

Went to tools/options/environment and changed value to "design light"
received message to "restart", clicked it to restart.

The application did shut down but did not restart. So I manually restarted to
application.

Then received the unexpected message. Learning from experience I choose
continue.

after restarting the next time I closed and reopened qt the same message appears.

Thought you should know about this situation. (also I chose to disable the first
time I saw this and that made Qt unusuable. I had to restore a container snapshot to
to get the application working. I am glad I took the snapshot.