Everywhere else that I edited text in /admin/customize/site_texts I see the results.
But for the flagging UI, e.g. /admin/customize/site_texts/post_action_types.off_topic.description , I’m still only seeing the default text. In fact, if I search for the default text to change, it doesn’t show up in search anymore since only my edited text will show in the search. But the flagging UI is just not using my text.
This is the case for all the text content in the radio-button areas, but I tested changing the “Take Action” button text and that worked.