If you want to join the conversations about new features or need troubleshooting advice, visit Get Satisfaction. Where can I discuss Thunderbird features or issues?.Please read these notes and the bug filing instructions before reporting any bugs to Bugzilla. Give us your feedback on Thunderbird at our GetSatisfaction site. Your feedback is essential to the project and makes Thunderbird better with every release. If you do find a particular profile data file is causing a problem, file a bug and attach the file, being sure to remove any private information as necessary. Migrate your settings files (Emails, feeds, etc) over one by one, checking each time to see if the problems resurface. Create a new profile by running Thunderbird with the -P command line argument, choose the 'Manage Profiles' button and then choose 'Create Profile.'. If you encounter strange problems relating to email, feeds or newsgroup messages, it is recommended that you try creating a new profile and attempting to reproduce the problem before filing bugs.

Disable the Extension/Theme that is causing trouble and then start normally.

When started in Safe Mode all extensions are disabled and the Default theme is used. Restart the email client in Safe Mode - select Help followed by Restart with Add-ons disabled. If you encounter strange problems relating to parts of the email client no longer working, the email client not starting, windows with strange or distorted appearance, degraded performance, etc, you may be suffering from Extension or Theme trouble.

Poorly designed or incompatible extensions can cause problems with your email client, including make it crash, slow down message display, etc.

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