Until you find the command, try using f6.  You will move through
different parts of the window such as to the address bar, and perhaps
to other parts including, I hope the notification.  Also, if you let
the full notification read when it starts, you will hear, at the end,
shortcuts to do what is offered.  Listen very carefully for such
information.  You may hear something like download, when you get an
update message, followed by control d and then not now, control n. 
I'm not saying these are the actual commands, but they are examples of
the kind of things you will hear.  This means I usually don't have to
look for the message, which is one reason I am giving you the f6 key
as a guess since I so seldom need to look for the message...

I've done quite a bit of searching out of curiosity since seeing your
message but I haven't found the command.

Gene
-----Original Message-----
From: Bob Jutzi
Sent: Tuesday, August 04, 2020 2:06 PM
To: nvda@nvda.groups.io
Subject: Re: [nvda] Error when using the latest NVDA Master with the
Enhanced Mozilla Add-in

The Windows 10 toasts shortcut works but haven't found the one for
Firefox notifications.

On 8/4/2020 2:32 PM, Joseph Lee wrote:

Hi,
Those are two completely different things. I know that Firefox has a
command to move focus to notifications, and for Windows 10 toasts,
press Windows+Shift+V.
Cheers,
Joseph

-----Original Message-----
From: nvda@nvda.groups.io <nvda@nvda.groups.io> On Behalf Of Bob Jutzi
Sent: Tuesday, August 4, 2020 11:30 AM
To: nvda@nvda.groups.io
Subject: Re: [nvda] Error when using the latest NVDA Master with the
Enhanced Mozilla Add-in

So how do we access those Windows 10 toasts which pop up when
connecting drives as well as those Firefox pop-ups notifications?

On 8/4/2020 2:28 PM, Joseph Lee wrote:

Hi,
The app modules Mozilla Enhancements add-on relied on are now gone
in NVDA alpha builds as part of a cleanup effort to remove outdated
code in NVDA, as these app modules were used in the day when NVDA
needed some workarounds to let users use Firefox and Thunderbird
more effectively.
Cheers,
Joseph

-----Original Message-----
From: nvda@nvda.groups.io <nvda@nvda.groups.io> On Behalf Of Bob Jutzi
Sent: Tuesday, August 4, 2020 11:26 AM
To: nvda@nvda.groups.io
Subject: Re: [nvda] Error when using the latest NVDA Master with the
Enhanced Mozilla Add-in

Sorry if this was previously addressed, but when running both V1.10
of the Mozilla Enhanced add-in and the latest NVDA Master, I am
getting an "error in app" when launching Thunderbird and Firefox.  I
tried both V11 and the newest developer release of the add-in which
result in the same error.

Bob