Not to cause any “offence”, but I think that “manoeuvre” would cause misspellings for you if you need to write something in American English, say a paper or a formal document. Best double check your spell checker locale, and make sure your words aren’t incorrectly “labelled” as you “centre” your text.

Having the default spell check as en_ca would be a problem through. I’d have an “axe” to grind in this case, as I challenge the “honour” of hunspell. I usually just manually choose metric units and a 24 hour clock on top of en_US.