Issue Can't copy big email to sent folder

[FredKT]

Hi everyone,
Working with thunderbird, when I send an email with a big attachment, the email is not copied to the sent folder. It's no big deal, but I'd like to understand why is that and if there is a configuration file I can tweak to increase the size I can send to the sent folder.
Hoping I'll learn a bit more...

 

[Bitpalast]

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