dir
The dir global attribute sets the direction of an element’s text (left-to-right or right-to-left).
Recommendation
It is highly recommended for an email client to support the dir attribute. It allows the author to set the direction of the text in the HTML message.
The direction of the text in the HTML message may not match the direction of the text in the email client UI. The HTML message may also have mixed directional text and the author would need in this case to specify the dir attribute on multiple elements.