Created attachment 2044 [details] exported MBOX file and the original claws folder For some mails the exported MBOX format seems invalid. I am not sure if it really is invalid - but it looks different from other MBOX files I know. Please see the file exported-folder.mbox in the attached archiv how such a file looks like. In there from line 2 to 17 there are unknown fileds. This format causes problems when exporting in other mbox-supporting software. The original claws-mail folder is ziped and untouched (absolute original without any anonymization of the header) also in original-claws-folder.zip.
Was reported in the past. https://www.thewildbeast.co.uk/claws-mail/bugzilla/show_bug.cgi?id=4253 Fixed in git but not released yet. So I keep this Ticket here open.
*** This bug has been marked as a duplicate of bug 4253 ***