just in case to make things clear, but you probably know this: when a contact is deleted from your allow list and from the block list then that contact is not blocked anymore either. To keep a contact blocked you need to keep it on the block list.
Messenger Plus! doesn't influence these things though.
The reason it popped up might be a record breaking lag, serverside
Too bad you don't have a record of this or you might have won the prize of strangest lag ever when you send it to MS... hehe.
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