Firefox 7 is released, new features in accessibility

Firefox Update 7 has just hit the net, and while it’s still hot, I wanted to share a few items specific to accessibility that are included.

First and foremost, we participated in the improvements to memory usage and speed. More accessibility classes participate in our garbage collection mechanism, reducing the memory consumption greatly. Long sessions with a screen reader running should no longer result in huge amounts of memory being consumed. This is especially evident if you run with multiple tabs and open lots of pages.

A bug was fixed that caused large additions to xul:tree elements to hang for long times when accessibility was turned on. This could be observed in add-ons such as Adblock Plus on occasion.

If role="presentation" has been specified on an element and this element is made focusable, for example by setting tabindex="0" on it, the role of presentation is now ignored, and an accessible is created for the element nevertheless. This is to avoid situations where one would suddenly land on a focused item for which there is no accessible. This was the cause for some screen reader confusion.

On HTML table elements, the way the summary attribute and caption elements were handled has been switched around. Now, if the caption element is present, it becomes the primary source (ARIA not withstanding) for the name of the table. summary is now being converted into the accessible description, which is used to communicate additional information to users. Only if the caption element is omitted, summary will still become the accessible name’s source. Until Firefox 6, summary would always become the accessible name’s primary source. This brings Firefox in line with other browsers. Also, if assistive technologies query for the relation between the caption and table elements, the relation is now LABELLED_BY instead of DESCRIBED_BY.

In addition, some crash bugs were fixed that were found in earlier updates of Firefox, so this version is not only less memory-hungry and faster, but more stable, too. Happy browsing!