Spell check menu appear and it usable with arrow keys
White default menu appear
From my experience most application combine both Cope/Paste menu and spell check at the same time
Probably related to another bug here: Right click on selected text that is misspelled word opens spell check menu
open a feature request to move the spell checker from a custom menu to the native right click menu.
Also we will migrate to another spellcker at some point in the near future. So this might get solved at that time.