This is an ongoing issue even with the latest Thunderbird 102.x where attachments downloaded via IMAP just won't save or will be corrupt which is a huge interruption to workflow or if you come back later to find out the file you thought you saved is invalid/corrupt and you have perhaps deleted the e-mail.
How to solve the Thunderbird filesize attachment issue?
1. Click on "Settings". then go to "General".
2. Scroll to the bottom to find "Conf........
This is one thing that has me wondering about SMF. It is apparently a known issue but in the latest version and new install nothing looked right because it was using http://127.0.0.1 to find everything! How on earth would it ever do this or think it is normal?
Excerpt of crazy html code it produces that causes the issue:
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