Ghost bars with revision 1667

yep, that happens to me all the time too, although usually not in the middle of the score. I notice it's happening to you right before a time change. Other people have reported similar anomalies, but in my experience, while annoying, the offending bar can be corrected with deletion.
What I would do is first add a measures in front of where the bad bar is, then select the new measure by clicking an empty spot on the staff. When you get the blue box, hold down, ctrl and shift and press the right arrow key. Doing this should give you a better idea of just where the bad bar is, and if there's only one of them. Then hold ctrl and click where the bad bar is being sure to click within the staff. If you can get the dotted blue outline, you can press delete and it should go away.

Chris,

MDMilford and Xavierjazz have both reported this to the forum (and apparently encounter it frequently) but the rest of us have not been able to reproduce the problem. Maybe with a little investigative work you can discover the steps that cause the problem. If so please share.

I've encountered this bug a few times. I happened to me recently when I tried inserting a measure. The bug seems to be related to some kind of file corruption which occurs when copy pasting (possibly also related to the changing of time signatures). Once the problem appeared I couldn't repair the file; with every change I made to the score, the problem got worse (more and more bars appeared). I tried copy pasting the score into a new file and the problem seemed fixed, but after restarting musescore the bug was also present in the new file.