Not being a DOM & CSS expert, I'm in need of some assistance further customizing what's displayed under Menu > Options > Search (or about:preferences#search in the address field) **without** using a third-party utility. Just to be clear, this is for an an enterprise deployment of Firefox versus customizing a single installation. Examples of what I'm looking to accomplish for our various markets: a) Set the default search engine (e.g.: Bing for some markets; Google for others; etc) b) Change the sort order (e.g.: Bing, Google, Yahoo for some markets; Google, Bing, Yahoo for others; etc.) c) Duck Duck Go, Wikipedia, Twitter and Amazon are of little to no value here so I'd like to remove them altogether. Unless I'm mistaken, I //believe// this can be done through userContent.css, but I need some guidance in how to accomplish this, or at least help on locating the appropriate resources that speak to this specific type of customization. Many thanks in advance for considering.