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Re: Resolving Lag With Jaws in an HTML Application Element Using Aria Live Regions

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From: Steve Green
Date: Feb 14, 2023 11:12PM

Now I understand and I can hear the difference between JAWS and NVDA. Unfortunately, I don't think you can make JAWS work the same as NVDA because they handle queued changes to the live region differently. JAWS queues all the changes and announces them all, which is why it says "long ramp" after you have moved to an empty space. By contrast, NVDA announces the most recent change and dumps all the previous ones. That is a desirable behaviour in your application, but it is not in some others. It would be nice if the author could control this behaviour, but it is not possible.

The ARIA 1.1, 1.2 and draft 1.3 specifications for live regions says "User agents or assistive technologies MAY choose to clear queued changes when an assertive change occurs. (e.g., changes in an assertive region may remove all currently queued changes)", so both JAWS and NVDA meet the specification in the case of an assertive region.

Curiously, the specification does not say what should happen to queued changes in polite regions, which is what you are using. Perhaps the specification authors thought it was obvious that the queued changes should all be announced since they are not time critical. If that is the case, NVDA's behaviour is incorrect. But we don't know because the specification doesn't say and it doesn't look like there are plans for it to do so.

Steve