I, too, am finding that Thunderbird 102.0 is corrupting email messages, replacing text with that from other messages or html formatting coding (also from other messages). This has happened for at least 6 messages. I have had to re-send them from my email web account. Other users are having the same problem (https://support.mozilla.org/en-US/questions/1381553 and https://support.mozilla.org/en-US/questions/1381629). In my case, and those reported in the other forum, the corruption appears to take place following Compacting of (at least) the Inbox. This appears to be a major problem with the 102 release. I am going to downgrade back to 91.11 until Mozilla fixes this (https://archive.mozilla.org/pub/thunderbird/releases/91.11.0/).

Upgrade to 102 was a mess... possibly a disaster. Extensions broken and email all scrambled. Now that i have upgraded, I cannot roll back to 91-x, since 102 transforms the file structure in the app. Sadly, it looks like it's goodbye Thunderbird.

UPDATE (7/9/22): I am not sure what happened or how, but I took another cut at TB and found the 102 loaded and opened up mail in an orderly and apparently correct way. An extension or two are broken, but so it goes with major upgrades. Stand by... but I think the kinks are working themselves out.

Yes, Jorge, it is a bit of problem. 102 was clearly not ready for release. To re-install 91.11 you need to install a new profile, which does unfortunately mean re-doing all your account settings, customizations and extensions. If you had a pre-102-upgrade profile backed up, the downgrade would be easier. I would hang about with TB, as they will fix the problems reasonably soon. Another option would be to use webmail for a month or so. By then some of the other extensions will become 102 compatible, too.

Someone has filed a Bug report, which appears to be the same issue (https://bugzilla.mozilla.org/show_bug.cgi?id=1777776) giving this a Priority P1 and Severity S1 rating.

NOTE: Bugzilla is not for feedback or support. For more info on Bugzilla etiquette, see https://bugzilla.mozilla.org/page.cgi?id=etiquette.html

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I have had dozens of emails corrupted, usually in the inbox. I found that I could repair the inbox and it did temporarily fix the corrupted emails, BUT IT REMOVED ALL MY TAGS - which I used to categorize messages and assign tasks. I lost a lot of info by doing this.

I'm still getting LOTS of corrupted messages. I didn't realize until I looked at this thread that they may be caused by compacting the folder. I will be careful or not do that at all until this version 102 is fixed. I discovered that I could create a new folder (named "CORRUPTED" ) and when I come across a corrupted email I move it to that folder. Sometimes I have more than 6 emails in it. Then I right click on that folder, choose Properties and Repair Folder. Then I move the emails back to their original folder. It's a pain in the ... but it does work.

I suspect it might be the size of my inbox. It was around 12,000 emails and I cut it down to less than 6000, but the problem still occurs. I just located the file and it appears to be over 1300MB. I will try to make it smaller still. I will try to avoid compacting the inbox until I'm sure this is fixed...

Hope this problem gets fixed soon! AP

I have the same issues. It is very bad to lose e-mail messages in this way. Please fix asap, and even SOONER !!!!