When I send a long email using Thunderbird, new lines are automatically added after sending the message. This makes it unpleasant to view the email for Gmail users, both on the phone and on the web interface. Three images are attached demonstrating this: One image shows how it looks in Thunderbird (text fits the window, good). One image (dark background) shows the message on the Gmail app on mobile (weird spacing, makes the message hard to read). The final image (white background) shows the message on the Gmail web interface, and again it adds new spaces and doesn't fit the text to the screen. Is there a fix for this in the Settings? I've tried playing around with the composition settings (using HTML and Plain text, but neither of those change it).