Reference: *Bi-directional Text Module at the W3C
The Bi-directional Text Module declares the following Common Attribute in the I18N Attribute Collection:
The Bi-directional Text Module declares the bdo
element, which is used where necessary to override the default
directionality of text, on a character-by-character basis.
Also, this module adds the dir attribute
to the I18N Attribute Collection.