Re: I wouldn't know, I can't even install it.
You need to submit a bug report. With some more details, like what this screen reader is. And that's a report to the creator of the packaged install, who is not necessarily anyone on the Mozilla dev team.
The installer evidently knows (or thinks it knows) about your screen reader, but the person who packaged it probably doesn't. It could very well be nothing more than a failure to check some tickbox in creating the package. Or something completely outside the browser: a system update to your toolchain?
Biting the hand that feeds IT
