Thanks for the explanations. I just noticed that sometimes the spellcheck highlights are visible in the notes but if I change note and come back to the original one they disappear. Sometimes they come back after 30 seconds automatically.
If I scroll a note with some spellcheck highlights sometimes the highlight disappear.
The behavior is not consistent at all and it is very slow.
Spell checking can take over 20 seconds to start on a note I just opened. It’s especially annoying, as I can’t know if there are no mistakes, or just the spellcheck hasn’t kicked in yet. Only checking the part of the note you are on also makes this worse, I have to wait after every scroll.
And I also noticed CPU spikes when I enabled spellcheck.