I have been using (and loving) Thunderbird in conjunction with Gmail for over a decade. Thunderbird on my desktop, and web-based Gmail on the laptop (and elsewhere). And I download full messages for offline access. For the last couple days, every time I open Thunderbird, it appears to delete all my emails (~150k), then redownload them all. As it does this, it keeps creating duplicates of all my folders. (I don’t have much in the inbox, but I have a byzantine structure of folders & subfolders.) So now I have “press clips” and also “press clips-1” and “press clips-2.” Only “press clips” has any messages. I am not sure what happened. I think I may have unintentionally toggled something improperly, either inside Gmail settings or inside Thunderbird settings. I was recently reconfiguring settings to bring additional accounts into Thunderbird (a second gmail account, and a protonmail account), so I was messing with settings both inside Tbird & inside the Gmail accounts. Those other two accounts appear to be stable (they also have virtually no emails, unlike my primary account). In examining Gmail settings, I was surprised to find that both IMAP and POP seem to be enabled—I had not expected to find this. My first thought was to disable POP, but I’m very wary of making changes, especially while Tbird continues to think and think and download and download. Of course it could be unrelated to my recent fiddling: maybe a recent update, or maybe unrelated corruption… Very grateful for any thoughts! I’m sure I omitted key salient info, LMK if so. Thank you! ------------- UPDATE: Uninstalled, erased remnants, reinstalled carefully. So far so good.