I've changed dozens of settings in about:config without issue ever since 2004 when about:config started being documented at MozillaZine: http://kb.mozillazine.

I've changed dozens of settings in about:config without issue ever since 2004 when about:config started being documented at MozillaZine: http://kb.mozillazine.org/About:config_entries http://kb.mozillazine.org/About:config_entries