AJAX error using media library in term

Problem/Motivation

I'm getting AJAX errors when trying to add a document to a term via the media library.

AJAX error message:

An AJAX HTTP error occurred.
HTTP Result Code: 200
Debugging information follows.
Path: /admin/structure/taxonomy_manager/voc/tags?ajax_form=1&_wrapper_format=drupal_ajax
StatusText: OK
ResponseText: 
Taxonomy Manager - Tags | Drupal
etc.

I've reproduced this error on a vanilla D9.4.8 site.

Steps to reproduce

1. enable taxonomy manager and media library
2. add a Reference > Media > Document field to the vocabulary using the media library widget
3. try to add a document to a term

(I noticed a couple old issues for this 3034237 3046752, but they were for 1.0.)