Allow to delete all messages in a specified range as before NEO.
Before NEO, messages were listed one "page" at a time (30 messages). By selecting the "all" button, all/just the messages on that "page" were deleted and not ALL the messages of the group like now.
We keep messages only for the last 6 months. So, as a moderator, I have to delete some hundreds of messages each month, clicking them one by one !
With the single page displayed now, it could be done using a range of messages determined by first and last message numbers.