Extraneous clefs added

I get extraneous clef and key signatures inserted during editing. I have not narrowed down what triggers this but it happens quite a lot. The clefs appear in all parts at once. MuseScore 4.0 on Debian Linux.

I can manually delete the extra clefs, and if I then save the file and reload it, they are not there. I have not found a way to delete the extra key signatures though they are not present after a reload.