Attachments dissappear when forwarding mails

When I’m forwarding mails, their attached Files disappear sometimes. This is pretty annoying when you have to save all the attachments somewhere just to add them to a mail again. Its seems to happen with 80% of the mails I try to forward but on some mails they’re kept attached.
First I thought its something about the maximum file size or some kind of safety measure but that got disproven when even an empty image file dissapeared.

Are you asking about attachments or embedded images?

Embedded images will not be included if you are forwarding the message as plain text.

Go to your settings and make sure both the new message format and reply format are set to HTML.

Attachments will be included regardless of whether the message is plain text or HTML.

i was talking about attachments.
They simply dissapear when I try to forward the mail the’re attached to.