On Sun, 23 May 2021 09:01:51 -0400
Hendrik Boom <hendrik@???> wrote:

> Interesting. Makes me wonder if, when firefox is started with a
> file:/// style URL it bothers to pass the content of that file to the
> remote firefox... Probably not

A commandline with a file:// reference will just start or switch to
Firefox in the same way that passing a URL will. Firefox would then
perform the action as-appropriate. So if it is given either of

http://example.com/foo.pdf

or

file:///path/to/foo.pdf

it will act the same, probably fetching and rendering the PDF inline.

(Although I don't know how, specifically, it loads or caches files from
remote or local sources and if it does it differently for those two
scenarios.)