Send Again option in Mail messes up layout

I'm trying to send a formatted email I received with inline encoded images using the option 'Send again' in Apple Mail. This messes up the entire layout, images are converted to attachments and margins are altered.

This used to be a great option to (re)send nicely formatted mails, but that's no longer true. Has Apple messed this up or am I missing something.

Same thing happens when forwarding. This should not happen when images are inline.

I'm on iMac M1, Sequoia 5.1