Possible Bug: Announce component - NVDA in Firefox reads such text twice or more

[orion-cengage]

Possible bug

Need to investigate and determine whether this is a bug or not. We received the following from an engineer:

Hi guys! There is a problem when I'm trying to use Announce component with the text with two dynamic values. NVDA in Firefox reads such text twice or more times, as you can see on the screenshot. I think that the problem with NVDA. NVDA+Chrome and JAWS+Firefox work as expected. Any thoughts about it?

BTW, if I remove aria-atomic="true" I'll see only some separate symbols, not the whole line repeated.