Hi, i wanted to configure firefox (proxies, homepage ...) from the command line ? Are there environment variable for such purpose ? I tried to change the prefs.js file for example, with homepage entry set to $HOME_PAGE and set the $HOME_PAGE variable to some other page; but the next time running it, Firefox always "updating ..." and reset everything, pointing the homepage to the mozilla website instead. Thanks in advance.

Try using user.js instead. From the mozilla website: [SNIP] Normal prefs are kept in prefs.js in the user's profile directory (which is overwritten by Mozilla every time a pref is changed), but here's a tip: prefs or other JavaScript that you don't want overwritten (e.g. comments) can be put in a file called user.js in the same directory, which is under the user's control and is read but never written by Mozilla. One caution with using user.js: prefs set to non-default values in user.js are also written to prefs.js, so removing or commenting out pref settings in user.js doesn't necessarily cause Mozilla to stop using your previous pref setting. If you change user.js and aren't getting the results you expect, be sure to check prefs.js to make sure it isn't setting a conflicting value. [/SNIP]