This is now implemented per:
https://github.com/discourse/discourse/commit/5865bd2abbac66e1ef5b475b491a2358a1d9d610
There are 2 caveats that I would like to address
- A “select all” “deselect all” button
- (Long term) allow search to … not be capped … at 50 and keep loading stuff.
This 50 cap makes “super ultra huge” bulk selection very annoying.