FYI, I had the same bug, until I deactivate the IMAP sync with folders created by https://www.findbigmail.com/
-- You received this bug notification because you are a member of Desktop Packages, which is subscribed to thunderbird in Ubuntu. https://bugs.launchpad.net/bugs/1229484 Title: Thunderbird freezes for 30s, rendering it unusable Status in “thunderbird” package in Ubuntu: Confirmed Bug description: Upon opening Thunderbird, the main Mail&News pane freezes while polling Inboxes on my 2 IMAP accounts. The main window freezes (graying out) for 30s, then comes back for 10s, then freezes again. In the 10s it is not grayed out, it is not really responsive. CPU is at 100%, and memory consumption is high. I have observed this already on Raring, but it is present in the Saucy version as well. I have tried to restart in safe mode, disabling all add-ons, without any improvement. On a side note, I have a lot of folders and my inbox has > 8000 messages, and I'm doing this over a high latency link (I'm in APAC, my mail server is in Europe, so ~350ms RTT). ProblemType: Bug DistroRelease: Ubuntu 13.10 Package: thunderbird 1:24.0+build1-0ubuntu1 ProcVersionSignature: Ubuntu 3.11.0-8.15-generic 3.11.1 Uname: Linux 3.11.0-8-generic x86_64 ApportVersion: 2.12.4-0ubuntu1 Architecture: amd64 BuildID: 20130917155107 Date: Tue Sep 24 09:00:25 2013 InstallationDate: Installed on 2013-03-19 (188 days ago) InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Alpha amd64 (20130318) MarkForUpload: True Profiles: Profile0 (Default) - LastVersion=Safe Mode/Safe Mode (Out of date) SourcePackage: thunderbird UpgradeStatus: Upgraded to saucy on 2013-09-23 (0 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/thunderbird/+bug/1229484/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp