On this subject - where do you find some of the files like preferences? and
user?

I have FX ESR, and don't want it updating. FX is sticking too much bloat in
there that you have to edit out. Same goes for TB. You can't do it through
about:config.

Here's the line entry before editing.
//@line 2
"e:\builds\moz2_slave\rel-m-esr10-w32-bld\build\browser\app\profile\channel-pref\
s.js"
pref("app.update.channel", "esr");

I found out how to edit in windows, but how to stop in Ubuntu?

I'm looking for browser and mail apps that don't update to add links to social
sites and other junk - just security. I like the extensions in FX and find them
too hard to use in Opera. I won't use Chrome.