It may be time for the Thunderbird team to look at all the folder name issue reported over the years, as per meta Bug 124287, and tackle them all ones and for all, for all types of account. I also found this guideline to workaround Outlook synchronisation issue with IMAP account, may be worth checking that Thunderbird is not affected by any of those as well! While at it... https://www.uk.forgetaboutit.net/wiki/index.php/How_to_prevent_Outlook_2016/2019_IMAP_sync_issues
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It may be time for the Thunderbird team to look at all the folder name issue reported over the years, as per meta Bug 124287, and tackle them all at ones, and for all, for all types of account. I also found this guideline to workaround Outlook synchronisation issue with IMAP account, may be worth checking that Thunderbird is not affected by any of those as well! While at it... https://www.uk.forgetaboutit.net/wiki/index.php/How_to_prevent_Outlook_2016/2019_IMAP_sync_issues