Hidden Formatting in Email Becomes Visible on Reply?

You can't rely on any formatting being preserved on a reply or forward. Was this "toggled off" button inside an HTML comment, or were you trying some other method to hide it?

If there's a toggle to hide the button, you might also want to try and clear the editable element for the button if that's possible (to get rid of the html). Simply hiding it with CSS isn't enough to actually eliminate it in situations like this, the code itself needs to be cleared (right-click on the editable area and choose "Clear Content").

When you receive an email, there's usually a bunch of styles that get dropped from the email based on which inbox service you use. Most (good) templates are coded with some different layers of code that work for Gmail, Outlook and the rest a little differently. Once you send the email and it ends up in a Gmail inbox, for example, it'll lose all of the code that was written for Outlook (b/c gMail doesn't recognize it as valid code) and some of the code will get interpreted to gel with gMail so it's not the same code getting forwarded as what came to the inbox originally.