Steps to reproduce:

1. Load https://w3c.github.io/aria-practices/examples//slider/multithumb-slider.html
2. Launch the attached pyatspi accessible-event listener
3. Adjust the slider thumbs on either of the Example sliders on the page

Expected results: Value-change events would be printed out by the listener every time the value changes

Actual results: No value-change events are printed out by the listener.

This seems to work with NVDA on Windows. When I adjust the sliders with the left/right arrow keys, NVDA reports the new value, which means a valueChange event is being fired. I'm not sure why this would be different with our ATK implementation.

It looks like we don't fire a numeric value change event if aria-valuetext is set. We instead rely on the text value change event. Unfortunately, the ATK code doesn't currently handle the text value change event for RemoteAccessible, even though it does handle it for LocalAccessible. The good news is that I'm unifying this event firing code in bug 1694573, so this should be fixed by that.

The URL provided in comment 0 is now dead. However, I tried both the APG Horizontal Multi-Thumb Slider Example and the APG Vertical Temperature Slider Example with Orca and both of them work as expected. The latter uses aria-valuetext.