The examples you provided work fine for me except “unactivated”, which I don’t think exists.
Yes, the correct word is deactivated. i.e. to make something inactive.
That’s very strange. What could possibly account for the difference? Why would my Obsidian’s spellcheck dictionary be missing many words that yours doesn’t?
Mines is similarly missing words like that. My uneducated guess is that they are word built upon a base word that is in the dictionary, but the dictionary only has a rudimentary selection for some reason. I am using Linux + Flatpak if that is meaningful personally