When trying to determine the source of an accessibility of web content there can be several levels where an issue might arise.
- Improperly or not implemented features in your own code/markup
- An issue with the browser not publishing to the accessibility api
- The Assistive Technology not using the information from the accessibility api
These can be tricky to determine, luckily there are a few tools available to help inspect what is being published to the accessibility api. If we can determine that the correct values are being passed to the accessibility api, then the issue is likely at the AT level.
Accprobe
Platform: WinXP, Win 7
http://accessibility.linuxfoundation.org/a11yweb/util/accprobe/#downloads
DOMInspector
Platform: Firefox Add-on (no accessibility info on Mac OS)
https://addons.mozilla.org/en-US/firefox/addon/dom-inspector-6622/
Accerciser
Platform: GNOME