Hi Martin, welcome to Permies! Sounds like you have some really useful skills.
I didn't realize that about the tea bags, but did figure out several years ago that both tea bags (all kinds) and
coffee filters don't decompose in the
compost. I assume it's because they are made out of some sort of polyester or artificial paper. Did you find any discussion about that here? I'd be interested to know what folks do with them other than throw them away.