[Accessibility] Using <h5>/<h6> for navigating between messages

[compulim]

Is your feature request related to a problem?

Windows Narrator doesn't support role="application". NVDA is buggy on it too.

So, navigating between messages using up/down arrow keys are frustrating to PWD as they need to turn off scan mode.

Describe the suggestion or request in detail

Add <h5>/<h6> header to message. So PWD use H key to navigate between messages. This would not need to turn off scan mode.

Describe alternatives you have considered

role="application", but it is not supported by Windows Narrator, and buggy in NVDA.

Additional context

No response