The first time you install firefox, both the keyword search in the address bar of the browser as well as the search box at the top right default to using Google as the search engine.

I find using the URL method (typing into the address bar directly) more useful. But since there are tonnes of search engines out there, if you want to explore a new search engine, you can easily change the default search engine that firefox uses.

In this example, the default search engine is changed from Google to Bing. It is very easy to do this and you just need to change a key value in the firefox configuration (the key collection).

Firstly, go ahead and type about:config and you will receive a warning that looks like the image below

Click on “Yes , I’ll be careful , I promise “ button. You will now see a lot of preference names and key values. In the Filter , type in keyword and you will see two options left.

The key which is of interest to us is keyword.url

Click on the keyword.url key in the list and right click and select modify. You will see the default value in it is the google search engine with the value http://www.google.com/search?ie=UTF-8&oe=UTF-8&sourceid=navclient&gfns=1&q= (this might vary depending on your system)

Replace that with http://www.bing.com/search?q=

You also need to make sure that the keyword.enabled boolean key value is set to true (this is done by default)

After that, press OK and restart the firefox browser (not always necessary, but a good practice). Now you are ready to test your tweak. Try typing in something in the address bar of the browser and press enter. You are taken to the Bing search engine with results. The same thing can be done to change to other search engines. You just need to change the keyword.url value.