Voiceover Navigation Doesn't Work On Tab Panels If Wrapper Has Aria-label

I recently noticed a very weird problem with VoiceOver's web navigation on tabs and tab panels. In particular, if the wrapper wrapping the tabs and tab panels has attribute aria-la

Solution 1:

If the two tabs contain just the strings "Tab panel 1" and "tab panel 2", then the issue appears to be fixed. Tested with OS X 10.11.1.

Yes, I know that the question is pretty old, but I'm adding my answer for future reference, just in case! :-)