From MozillaZine Knowledge Base
When a Mozilla application starts up or creates a new window, this preference is consulted for a chrome URL to be used for the window.
Possible values and their effects
chrome:// URL to be loaded when Mozilla starts as the application chrome, and to be used when new windows are created. The default is
chrome://browser/content/ for Firefox and
chrome://navigator/content/navigator.xul for Mozilla Suite/SeaMonkey.
- Setting this preference incorrectly can break your browser, preventing any new windows from appearing until it is set back. Use caution when modifying its value.
First checked in
Has an effect in
- Mozilla Suite (all versions since M16)
- Mozilla Firefox (all versions)
- Mozilla Thunderbird (all versions)
- SeaMonkey (all versions)