I usually do offline validation which could also be done in a bash script but if you're looking for an online service a quick google search returned https://teibyexample.org/tools/TBEvalidator.htm which also reports the wrong tei:extent
Using Zotero 6.0.21 I can add some issues in this context:
A) Right-Click/Export Library…
All options checked (Export Notes, Export Tags, Generate XML IDs, Full TEI Document, Export Collections)
This returns a well-formed TEI, bu…
Thanks for the clarification, is there any way of making a CSL type replace intact inner quotations marks according to `open-inner-quote` and `close-inner-quote`?
E.g. output a title saved as: Something about „Worktitle“ and other things