.attr('checked') does not work as expected for application/xhtml+xml documents

[kieran@…]

It is impossible to use .attr('checked') to read and modify checkbox states for documents that have the application/xhtml+xml content type. Instead, it returns "checked" or "undefined" depending on whether the checked="checked" attribute is specified for the tag. A boolean true/false was expected.

If the document is sent as text/html, it works as expected.

I have tested it in both Firefox and Google Chrome with the same result.

Example: ​http://caffie.net/checkbox/index.xhtml

[anonymous]

Try using ​http://api.jquery.com/checked-selector/ instead

[dmethvin]

The true/false magic for .checked is a DOM1 HTML behavior and not supported in XHTML.

Dup of #4283 where it is discussed ad nauseum.

[dmethvin]

Duplicate of #4283.