In iOS Messas, there is the feature where you can tap and hold a message and it comes up with Copy More. Tap More and in the top left you get Delete All or you can tap the little circle on the left side of each message you want to delete, then tap the trash can in the bottom left to delete selected messages. I like to keep the list of names I message most in Messages, that way I don't have to start a new message and find the address of the person I want to message. So, I periodically go through and delete conversations in Messages. Problem, I can delete 2-3 conversations before the Copy More stops coming up. To fix this I have to reboot Messages. It becomes annoying when there are 6-8 people I'm clearing out conversations from. I'm guessing this is an under utilized feature of Messages because I have yet to find anyone talking about this not working. Apple has yet to address or fix the bug.
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