Like any other email client, the Mac Mail provides you with the feature to add customized email signatures to your email messages. Sometimes, when your recipient gets your email, the signature that you have inserted would appear to be double the size of the original one (that you sent). The text within your email will display with the normal size. However, the signature size would be twice the original one. If this is your problematic situation right now, the following method that has worked fine for many users will help you fix the Mac mail signature formatting problem issue as well.
You have now solved the Mac mail signature formatting problem using a few simple steps.