Summarized test results:
HTML5, the bdo element

Intended audience: users, XHTML/HTML coders (using editors or scripting), script developers (PHP, JSP, etc.), CSS coders, Web project managers, and anyone who wants to know how language declarations work in current browsers.

Updated

These tests check whether user agents apply directional rules as described in the section about the bdo element.

Note that the snapshot summaries of these test results are for released versions of the browsers tested. Versions that are still in development may provide better support for these features. The tests themselves do not test any vendor prefixes.

results

To see the test, click on the link in the left-most column. To see detailed results for a single test, click on the link in the right-most column. To submit test data for a single test, click on the link in the right-most column and then follow the link on that page.

The tables show the latest results from the W3C Test Framework. Below the tables are summaries of the results at a given date. The table data may be more up-to-date than the summary. The tables may also contain some incorrectly scored tests, and tests that relate to non-released versions of browsers. These are not included in the summary.

Basic direction overrides

Snapshot summary, 2013-07-03
Firefox 21.0, Opera 12.15, Internet Explorer 10 & 9, Chrome 27.0.1453.116, Safari 5.1.9

The bdo element with a dir attribute works as expected on all browsers.

When the bdo element has no dir attribute, although the spec says Authors must specify the dir attribute on this element, with the value ltr to specify a left-to-right override and with the value rtl to specify a right-to-left override, only Safari followed the spec. All other browsers tested applied an override consistent with the direction of the parent element.

Assertion Gecko Presto Trident WebKit Detailed results
bdo, dir ltr The bdo element with dir set to ltr causes all contained text to ignore the bidirectional algorithm and displays all characters from left to right.
bdo, dir rtl The bdo element with dir set to rtl causes all contained text to ignore the bidirectional algorithm and displays all characters from right to left.
bdo, no dir, rtl context The bdo element with dir not set will not override the Unicode Bidi Algorithm.
bdo, no dir, ltr context The bdo element with dir not set will not override the Unicode Bidi Algorithm.