iMovie: Cannot create new projects in external libraries
I'm unable to create new projects in new iMovie libraries on external drives. I noticed the problem a couple of weeks ago, when I finished projects in - let's say - October library, and I wanted to set up a new November library. In any new library on any external drive imported files are blank icons, with a message "filename" is missing. Try reimporting the original source media.
I tried different external drives, I tried reinstalling iMovie, but to no avail. I also cannot find anyone with a similar problem.
Any suggestions?
MacBook Pro 13" M1 2020, iMovie 10.4.3, Tahoe 26.1