Live Region: Value in aria-live has no effect

Summary

Save as HTML file:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="utf-8">
    <title>live region</title>
</head>
<body>
    <div aria-live=assertive id=1></div>
    <div aria-live=polite id=2></div>
    <div role=alert id=3></div>
    <div role=status id=4></div>

    <button onFocus="document.getElementById('1').innerHTML='region1';">live region with aria-live=assertive</button>
    <button onFocus="document.getElementById('2').innerHTML='region2';">live region with aria-live=polite</button>
    <button onFocus="document.getElementById('3').innerHTML='region3';">live region with role=alert</button>
    <button onFocus="document.getElementById('4').innerHTML='region4';">live region with role=status</button>
</body>
</html>

Navigate to all buttons

Expected result

Correct output according to specification (https://www.w3.org/TR/wai-aria-1.2/#aria-live)
- role=alert and aria-live=assertive with "highest priority and should be presented the user immediately"
- role=status and aria-live=polite "at the end of speaking the current sentence or when the user pauses typing"
Consistent output between browsers

Actual result

Firefox, IE 11, Chrome: value in aria-live has no effect. The output is always after the other output of the screenreader (i.e. assertive is also output like polite)
IE 11, Firefox: Only alert is output at the beginning
Chrome: Also alert is output at the end

Additional Information

JAWS version and build number

JAWS 2019.1907.42

Operating System and version

Windows 8

Browser and version:

Chrome 76.0.3809.100 Firefox 68.0.2 Internet Explorer 11.0.9600.19431

Testing using the latest version of JAWS (2020.2006.12), Chrome (84.0.4147.89), Firefox (78.0.2), IE11 (11.959.18362.0) on Windows 10 produced the following results:

JAWS+Chrome: Button name announced before live region for all buttons. Alert role is not announced.
JAWS+Firefox/IE11: Button name announced before live region except for button with alert role. Role is announced.

By comparison, NVDA (2020.1) announces the live regions first before the button names in all instances.

NVDA+Chrome: Live region announced before button name for all buttons. Alert role is not announced.
NVDA+Firefox: Live region announced before button name for all buttons. Alert role is announced.

In summary, updates made in aria-live="assertive" regions are not immediately announced in JAWS with any browser and role="alert" is not announced in Chrome as expected. Detailed information on live region support can be found on the Accessibility Support site.

FreedomScientific / standards-support