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• mail.imap.auto_unsubscribe_from_noselect_folders  Default and desired value: true
• mail.server.default.check_all_folders_for_new  Default false.  Setting it true avoids the user having to wait for mails to be downloaded on opening folders other than the Inbox – but it may degrade overall performance, especially when Thunderbird is started.  When the IMAP server is local it should be OK.  In case of several IMAP servers, the setting can be made for specific servers using mail.server.server<n>.check_all_folders_for_new

Too many simultaneous connections

In case of trouble with "too many simultaneous connections" (common with bluelight@auroville.org.in), reduce the "Maximum number of server connections to cache" (TODO: presumably on all clients); the default value is 5.  Account settings > Server Settings > Advanced.

Usage

Backup considerations

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