Comment 123 for bug 233901

Currently the preference (in all.js) reads
chrome://navigator-region/locale/region.properties
This means that the file in FR.jar (or whichever region you have installed) has
the actual value used as the default home page.
Now you need to create your own properties file, with the one line
browser.startup.homepage=www.int-evry.fr
Then just use autoconfig to set the preference to a URL to your properties file.
If you distribute the properties file with the browser then you can use
resource:///region.properties or alternatively you can use a file URL such as
file://///smbserver/share/region.properties or even a remote URL such as
http://webserver/region.properties or ftp://ftpserver/region.properties