Undo of a new keyword added to a photo doesn't remove the keyword from the Keyword List

Adding a keyword not currently in the Keyword List to a photo and then doing Undo correctly removes the keyword from the photo but incorrectly leaves the keyword in the Keyword List. 

This is important to users maintaining a carefully controlled vocabulary. If they mistype a new keyword and then Undo, leaving it in the Keyword List will make it likely that auto suggest will cause them to add the mistyped keyword to a future photo.

Back in LR 9.2, LR's product managers recognized that it was important that Undo remove the newly added keyword from the Keyword List as well as the photo. Previous versions would remove the keyword from the Keyword List but not the auto-suggest list, and LR 9.2 fixed that, also removing the undone keyword from the auto-suggest list:

https://community.adobe.com/t5/lightroom-classic-bugs/p-deleting-a-keyword-from-the-keyword-list-doesn-t-remove-it-from-auto-complete/idi-p/12249083

From version 9.2 through version 12.1, Undo would remove the newly added keyword from the photo, the Keyword List, and the auto-suggest list. But LR 12.2 broke Undo, leaving the newly added keyword in the Keyword List and the auto-suggest list. That misbehavior continues through LR 13.2.

To reproduce in LR 13.2 / Mac OS:

1. In Library, select a photo.

2. In the Keywording Panel, enter a keyword never before typed in that catalog (e.g. "xyz5293").

3. Do Edit > Undo.

4. Observe that the keyword is removed from the photo (correct) but remains in the Keyword List (incorrect) and thus in the auto-suggest list.