Hi! Thank you very much! This parameter (check_all_folders_for_new) was actually the solution to my problem that not all new mails were reported.
Regards Thorsten > On 28/12/2020 09:44, Matthias Fechner wrote: >> Am 27.12.2020 um 16:11 schrieb Juri Haberland: >>> I can't help you with your performance problem, but for Thunderbird to >>> check all folders, you need to set "mail.check_all_imap_folders_for_new" >>> to 'true' in the Thunderbird config editor. >> I think the setting is: >> mail.server.default.check_all_folders_for_new;true > Both settings exist, but you are right, my setting is deprecated: >