Comment 1 by jteh on 2013-07-22 06:07
Your tab panel is marked as a live region, so any changes therein are reported accordingly. For some reason, selecting a tab causes show and text inserted events to be fired as if all the content was just inserted into the DOM. I'm not sure why this is (whether it's something your code is doing or whether it's specific to Firefox). Regardless, I'm curious as to why the tab panel is marked as a live region at all. It's not something for which one generally cares about all changes, so I'd argue this is unnecessary/incorrect. The tooltip is already provided via aria-describedby, which can be queried on demand by the user and is reported if the user moves focus to the tab.

Marking as invalid because this isn't an NVDA issue; NVDA is handling the events for the live region as fired by Firefox.
Changes:
Added labels: invalid
State: closed

Comment 2 by michaelvogt on 2013-07-22 06:53
Thank you for looking into this problem and your comment.

What would I need to do to find out about such superfluous events arriving at NVDIA myself? Is there some kind of log output from NVDA with this information?

Comment 3 by jteh on 2013-07-22 23:39
Initially, I thought you were intentionally adding aria-live="polite". However, it seems Firefox may be doing this implicitly. There is a bug to have this behaviour removed: MozillaBug:896400.