NVDA doesn't announce matTooltip in IE 11

[diminutivesloop]

Bug, feature request, or proposal:

Bug

What is the expected behavior?

matTooltip text should be announced by screen reader when associated control is focused.

What is the current behavior?

In IE 11 matTooltip text is not read by NVDA.

What are the steps to reproduce?

https://stackblitz.com/edit/angular-5axarj

Which versions of Angular, Material, OS, TypeScript, browsers are affected?

Angular 6.0.9
Material 6.4.0
Browser: IE 11
Screen Reader: NVDA 2017.4

[crisbeto]

I can reproduce the issue as well. @jelbourn by the looks of it, the issue is with the AriaDescriber which has display: none and aria-hidden that cause IE not to read out the messages (for reference). We can hide the element using cdk-visually-hidden, but if we were to remove the aria-hidden, the messages will now become part of the page, which means that they'll be read out when the user uses the arrow keys. I don't see a nice way around it, aside from only adding aria-hidden on non-MS browsers.

[jelbourn]

What happens if the parent element has aria-hidden="true" and the child description has aria-hidden="false"?

[crisbeto]

The message doesn't get read out in this case either.

[jelbourn]

Yeah, this seems like a case where it makes sense to do something different for IE11 then.

[diminutivesloop]

Any idea when a fix for this will be merged?