We need to invalidate the cache otherwise each page needs to be purged manually and often the frontend JS breaks.
Obviously we don't want to cause a massive spike in load so we only want to do it for necessary pages. In this case it should only be when the Lexeme frontend pages change.
Probably should be looked at after T198455
IIRC we have had the same in items and introduced a cache epoch setting (?) that we increase when needed.
So we used to a general mediawiki cache epoch, but we can no longer use that.
We found that out as part of T197222
Just a thought, we can define versions and increment it every time we change templates.
Yes, and then we essentially just have to use the reject parser cache value hook when new templates are used?
We removed this from the campsite and marked as stalled during task breakdown today.
It was created as part of T209931 but then was not needed, so was not done.
This would still be a good thing to do in the future to avoid further issues when changing these things.
It's likely that if the lexeme UI is reworked that this will no longer be relevant.
So moving to freezer for now