Mouse randomly stops highlighting

[Lillie_Harris]

I think in some cases, the Instant Print Preview/Hide Invisibles key can get “stuck”, e.g.

Showing notes in voice colors

Hide Invisibles can occasionally get stuck. Is there a possibility you’re using that key inadvertently, possibly as part of another shortcut? It’s the backslash on my keyboard but depending on keyboard layout it may be different - check Preferences > Key Commands.