What does this signpost mean?
I don’t know whether it helps to point out that the file started life as a MusicXML import, but all the instruments have been changed.
What does this signpost mean?
When you select it, what does it say in the status bar at the bottom of the project window?
My guess is figured bass.
My guess, too, though it’s a bit odd to see it on a viola!
You both guessed correctly! I had taken a quick glance at the status bar, but had failed to spot the description at the bottom for some reason.