In Classic, email trails were converted to rich/plain text. In Lightning the previous emails in the trail remain as HTML. This means that users get an error message when trying to reply (normally on the 3rd reply but not limited to). Is it possible to either revert the email trail for replies/forwards rich/plain text but still keeping the new message as HTML or - if not - increasing the HTML limit? What we can and can't do will help us to determine how we create new email templates moving forward.
Please ADVISE .