You just think they don’t work because nothing appears to change. I don’t know what a sighted person may see, but if you want to see progress, after you issue the download command, go into the about dialog, alt h followed by a.  Then check to see if browse mode is on.  Use NVDA key space.  If it isn’t on, turn it on.  You can now move around the about page as you would any web page.  You will find a line or two near the top of the page that tells you what is going on regarding the update. 

 

As I recall, if you keep causing the line to read, it will say, after a time, something about restarting Firefox to update and you will hear a command to do so and there will be a button you can activate as well.

 

Gene