From ARIA issue 451 raised by @fstorr.

The element has an incorrect default ARIA role of progressbar which causes some assistive technology (I've tested in VoiceOver on OSX 10.11) to announce the element as a "progress indicator" and the value of the element as a percentage rather than the defined value (for example "80%" instead of "4 out of 5").

The HTML AAM specifies no corresponding ARIA role for meter, but it looks like the separate mappings for meter in MSAA+IA2, UIA, and AX reflect the progressbar role and progress element, which isn't correct.

@asurkov, the definition for ROLE_SYSTEM_PROGRESSBAR is wrong for meter. The meter element has semantics distinct from progressbar. Any suggestions? I note that ATK is using ATK_ROLE_LEVEL_BAR (as recommended in ARIA issue #150), which is certainly closer to the semantic for meter, but IA2 doesn't have a similar role.

@cyns, you raised the question of UIA mapping for meter in ARIA issue #344. What's there looks to be the same as the mapping for the progressbar role. How do you suggest UIA distinguish the meter and progress elements?

@cookiecrook, same question: the AX mappings for meter and progress elements are the same and don't reflect the different semantics. Is there a better role/roledescription for meter?