Re: Forsooth!
I believe "thee" is correct as I was using it - https://www.merriam-webster.com/dictionary/thee - but I'm not an expert.
MW says, correctly of course, that it's the objective form. You were using it as the subject. When I grew up in Yorkshire second person singular was still in current use by older gernerations so, give or take the dialect pronunciation, it's second nature.
Biting the hand that feeds IT
