Wilt ge een tas koffie?

I’ve never used ‘gij’ before, but shouldn’t this be ‘Wil ge’, not ‘Wilt ge’? Don’t you need to drop the t/d from the verb in when asking a question like this?

“ge” is normally used in Flemish, and in some regions in the south of the Netherlands, as a polite version of “je”/“jij” (similar to “u” in the rest of the Netherlands).

While it does follow the second person singular in the cases where the subject precedes the verb, it does not lose the “t” in the inversion cases (where the verb comes first or in questions) like the informal “je”/“jij” indeed would.

E.g.

Informal:
Q: Wil je een tas koffie?
A: Je wilt een tas koffie!

Formal:
Q: Wilt ge een tas koffie?
A: Ge wilt een tas koffie

P.S. “tas koffie” also suggests Flemish or Dutch from Brabant/Limburg, since in the rest of the Netherlands “tas” would suggest a “(hand)bag”/“purse”, and rather “kop” (or the diminutive “kopje”) would be used.