I get a lot of SMS from gmail and often filter them, select all then mark as read, so as to keep them archived, but out of my unread inbox. Something lagged, or otherwise bugged out and this time after clearing the filter I noticed ALL my inbox was marked as read. Is there any way to undo/reverse this? I even have hourly backups of the INBOX file, but after restoring it, it still looks like everything is read (maybe the GMAIL side is syncing them to be marked as read?). I use read/unread as a way to keep track of what I have and have not responded to yet, so this is quite the blow to my workflow and would potentially take hours if not more to recover manually from. If there is no way to reverse this, how can I ensure this won't happen again?