Circles over stems - feature I've never seen before
I was editing a score this morning, and then I noticed some circles had appeared round the stems of a timpani part. I've never seen anything like that before.
I'm not sure if that means anything to percussionists, but I can copy the notes to other parts, so probably not a symbol specific to timpani.
I've never seen anything like this before. Does anyone know what these mean and how did I create those?