When deleting an attachment it seems gone, but is in fact replaced with a numbered copy of the same file, as visible by clicking on the mail again. I accept that removing attachments will break the signature, but other than that it should be possible, or there should be a warning.
In fact, renumbering of attachments happens also by just viewing them repeatedly. This likely causes multiple copies somewhere, reducing disk space.
Also, renumbering is not done correctly in a case where there is multiple dots in the file name, like a date. See attached example:
I'll go for a warning / error for now and see if I can fix the renumbering.
We can't really remove attachments. Maybe we could persistently hide them but that would probably defeat the purpose of removing them (making the mail smaller).
- For Signed - Not encrypted mails we could offer to remove the signature when removing an attachment.
- For Encrypted Mails there is a long standing feature request to allow "permanent decryption" then you could permanently decrypt and remove an attachment. Anything else for encrypted Mails like "re encrypting the message without the attachment" is complex and is currently far away.
Normal Prio as this is not a regression and might not make it into a 3.1.0 release.