I have 2 IMAP accounts configured, and noticed that the CPU hogging / hanging is definitely related to the number of messages in a mailbox. I haven't found a lower bound that causes the issue, but mailboxes with e.g. 20000 or more messages of cronspam were definitely part of the problem. Removing these messages and/or partitioning them e.g. chronologically may be a viable workaround.
Testing with "insanely large" mailboxes should definitely be part of finding the problem ;) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/927515 Title: Thunderbird stuck at 100% CPU To manage notifications about this bug go to: https://bugs.launchpad.net/thunderbird/+bug/927515/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs