Thunderbird Community Forum

Hello all!

I use Thunderbird as a local archive for my email. I have two accounts in the application: my home email via my ISP (POP) which I predominately use and my gmail (IMAP) which I don't generally use. There are years of messages in folders and sub-folder under the POP account, but nothing under the IMAP.

I’m up to date with Thunderbird at v140.1.0esr (aarch64) on my iMac with Sequoia 15.8.

On 07/22/2025 I went to download some messages via my ISP POP account and saw that a whole bunch of my email folders no longer had any subfolders and were empty of any messages. Some were also duplicated. Please see the attached image.

I haven’t changed any settings in years, and I do not have any add-ins. One of the nice things about Thunderbird has been its solidity and simplicity.

After every session, I would empty my trash and compact.

Suddenly my email seems to be gone along with sub-folders while top level folders are duplicated.

Wondering if anyone has any suggestions on how to troubleshoot this? Since I don't do anything fancy with the application and with the suddenness of this issue, I can't image I'm the only person having it? I’m quite concerned I may lose many years’ worth of messages.

Thanks much in advance! CPRoot

Hello,

I have Thunderbird version 140.3.1esr (64-bit) , everything looks good with multiple accounts , except there is a big issue on reading emails: 1- when I double click on any email I get the email as edit mode and not like when I press F8. when I press F8 the email looks normal, but when I double click not.

2-Some emails received as HTML format reads the body as HTML attachment. 3-Some emails show part of the email and not all text with HTML format.

Hope the developer know about this issue and someone can help me to solve this issue if work around.

Thank you

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