By default if one forwards an email, attached files are unchecked. One has to check those for files to be included in an email.
IMHO it’s only natural to forward email received with attachment to forward with attachment. Current setting raises issues when someone forgets to check attachment files when forwarding.
Especially if the email has a lot of text in it, then one doesn’t even see the bottom of the form, and there is nothing to remind that attachments have to be checked.
Moreover it might be a better thing to move option-checkboxes from the bottom to the top and having “advanced” collapsable pane for that, which would collapse if form takes all screen open if form is is little.
Bottom option-checkboxes:
