User Agent Variance in Applying Bidi Algorithms

When considering bidirectionality in documents you should be aware of two problems, the first being that there exist different rules for directionality, based on the character itsself, the possible usage of characters LEFT-TO-RIGHT MARK, Unicode CP 8206_dec (symbol , abbreviation: LRM) and RIGHT-TO-LEFT MARK, Unicode CP 8207_dec (symbol , abbreviation: RLM), the use of the HTML dir attribute, and the use of the CSS unicode-bidi attribute. The second problem is, that depending on the browser you use, you will get different results when these rules are applied.

The following illustration shows how a combination of all these rules is rendered in three different browsers. Note the considerable difference and that only Mozilla applies both normal and embed values for the CSS unicode-bidi attribute.