Found in

• 109.0a1 (2022-12-07)

Affected versions

• Firefox Nightly 109.0a1 (2022-12-07)

Affected platforms

• Ubuntu, Mac

Preconditions

• Enable Orca - Ubuntu
• Enable Voice over - Mac

Steps to reproduce

1. Reach url: data:text/html,<input type='datetime-local'>
2. Reach each field from the Date picker using Tab key.

Expected result

• Each field should be read out loud correctly by the screen readers i.e. Month spin button, Day spin button

Actual result

• Orca reads: mm spin button, dd spin button.
• Voice Over reads: nan month stepper, nan day stepper

Regression range
This issue is not a regression.

As mentioned above, this is a preexistent behavior and it is also cross-browser behavior for fields within date/time/datetime-local inputs, at least on macOS - both Chrome and Safari keep their silence when these spin buttons are focused with VoiceOver.

That would be a nice thing to have though, to have them announced in the future.