Re: Retrieving a webpages shows a blank screen when a 4xx HTTP status is returned. Not helpfull.

Dave,

> Except, it seems, it will run even with js tuned off, according to
> that bug, which I think is odd.

I asked myself the same question when I started to use GM on FF that had JS 
disabled, and concluded that the GM scripts where probably being run on a 
different "level" than the scripts in the page itself.

> But if background scripts don't work with js turned off (which
> is that bug, and is why the http respinse addon fails) then GM
> ought to fail too.

There is a difference: as far as I can tell GM is an old-style XUL plugin. 
The support for it most likely goes over a different codepath than that of 
the "new" style add-ons.

> You said you have GM. Does it work it v52?

Yes, GM works on FF v52.5.0  (I would have removed it if it would not :-) ).

> (In fact, does any WX addon work in v52?).

WX ?  I just did a quick google , but it didn't give me an explanation for 
it.

But if you mean the "new" style add-on mechanism, I tried some example 
add-on tutorial that only used a content script, and that worked - with JS 
being disabled.

Regards,
Rudy Wieser