When you access websites in the Firefox web browser, you usually enter the domain name like www.trishtech.com in the address bar and press Enter. But when you perform searching and access various other parts of a website, the URL changes and might contain many different terms that are used internally by the website mainly for tracking the website usage. For example, if you access Facebook website in your web browser it appends a parameter utm_source to the URL. This and other similar parts of the URL convey no meaning to the user and end up making the URL very confusing.
You can clean-up the URL in the Mozilla Firefox web browser using an add-on called Pure URL. This extension for Firefox removes all the unnecessary parts in the URL and makes it look cleaner. But it does not mean that those parts are not sent to the web server when accessing a website. It does not interfere in the way a website loads in any manner. The changes in the URL that show up in the address bar are purely aesthetic in nature.
Pure URL does not have any kind of interface or visible options that you access from the Firefox browser’s window. But you can change some settings for this extension by visiting the about:addons page in Firefox and then accessing Pure URL options. You can edit the garbage fields list and add or remove the items from there. You can choose whether you want to fix outgoing HTTP requests or the links inside a web page. By fixing, it means that it will remove all the garbage parameters (used for tracking how a visitor accesses a website) from these links or HTTP requests.
Conclusion: Pure URL is an extension for the tracking conscious Firefox users who want to keep the tracking down by cleaning the tracking parameters from the URL.
You can download Pure URL extension for Firefox from https://addons.mozilla.org/en-US/firefox/addon/pure-url/.