For the love of all that's free/open:
please make it so that next time (T177940) I have to clean up a feedback board like I did in https://www.mediawiki.org/wiki/VisualEditor/Feedback,
I can select threads and mass-hide them, and not consider resigning in despair.
(The reasons why almost none of those are hidden immediately, but simply closed, is the vague hope that who posted passes again to see what happened to their feedback, as sometimes we also reply to OT feedback with pointers.)