Alternatives to Theme Font size changer Firefox plugin?

[Tim]

Allegedly, on or about 06 February 2016, Sam Varshavchik sent:
> The top-ranked comment on that extension page suggests hacking
> "userChrome-example.css" in ~/.mozilla/firefox.
> 
> $ find ~/.mozilla/firefox -name userChrome-example.css -print
> $
> 
> There goes that idea. 

It may be one of those files that doesn't exist unless you create it.
Or, there may be a default in the program's directory, that gets used
until you put one in your homespace.

And sometimes you find that the filename has changed, slightly, between
versions.

-- 
[tim at localhost ~]$ uname -rsvp
Linux 3.9.10-100.fc17.x86_64 #1 SMP Sun Jul 14 01:31:27 UTC 2013 x86_64

Boilerplate:  All mail to my mailbox is automatically deleted, there is
no point trying to privately email me, I only get to see the messages
posted to the mailing list.

Windows (TM) [Typhoid Mary]. They refuse to believe that there's
anything wrong with it, but everyone else knows Windows is a disease
that spreads.