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List of "about:config" commands

  • 3 replies
  • 12 have this problem
  • 254 views
  • Last reply by cor-el

ET
ET

I want to be able to really fine tune/customize firefox, but many of the changes I want to make are only available thru "about:config". An example of such a change -- how to force new tabs to open blank -- took quite a bit of searching and knowing what question to ask or how to phrase it. Is there a list of all the "about:config" commands, and if so, where do I find/get them? Is it just a printable list (acceptable, but just...), a basic searchable database (better, but probably still have to know/phrase a question), or best yet, a keyword searchable db with both of the previous options? Also, is this putative list version specific, or is it constantly updated with a mix of old and new commands? I realize the risk of severely damaging the firefox installation, and am prepared to take it, as I think I'm reasonably cautious, and would check out any truly questionable changes before making them.

I want to be able to really fine tune/customize firefox, but many of the changes I want to make are only available thru "about:config". An example of such a change -- how to force new tabs to open blank -- took quite a bit of searching and knowing what question to ask or how to phrase it. Is there a list of all the "about:config" commands, and if so, where do I find/get them? Is it just a printable list (acceptable, but just...), a basic searchable database (better, but probably still have to know/phrase a question), or best yet, a keyword searchable db with both of the previous options? Also, is this putative list version specific, or is it constantly updated with a mix of old and new commands? I realize the risk of severely damaging the firefox installation, and am prepared to take it, as I think I'm reasonably cautious, and would check out any truly questionable changes before making them.

Chosen solution

You can also check the comments in the Firefox source code for the default prefs.

  • resource:///defaults/preferences/firefox.js
  • resource://gre/greprefs.js

Note that there also hidden prefs that do not exist by default and have a default action/value hard coded.
Such a pref needs to be created if you want to make use of it.

See e.g.:

Read this answer in context 👍 5

All Replies (3)

philipp
philipp
  • Moderator

hello eviltwin, here is a site which covers many preferences from about:config (however it's neither complete nor always up-to-date): http://kb.mozillazine.org/About:config_entries

mozilla's own documentation in this regard is rather limited currently: https://developer.mozilla.org/en-US/docs/Mozilla/Preferences/Preference_reference

ET
ET Question owner

Thanks for the info, phillipp. I'll be looking these sites up. Like you say, they may not be complete, but they're definitely more than I had before, eh? I'll leave the question open for a while longer, just on the off-chance that someone may have more info yet, although I suspect you may have mined all the ore there is on this one already ;->. Thanks again!

cor-el
cor-el
  • Moderator

Chosen Solution

You can also check the comments in the Firefox source code for the default prefs.

  • resource:///defaults/preferences/firefox.js
  • resource://gre/greprefs.js

Note that there also hidden prefs that do not exist by default and have a default action/value hard coded.
Such a pref needs to be created if you want to make use of it.

See e.g.: