You must have hit Shift+Ctrl+Delete a lot of times on Firefox for clearing your Browsing History. The browser history includes Browsing and Download History, Cookies, Cache, Form and Search History etc. Cookie is generally a piece of data that may include a user’s authentication data, preferences etc. Sometimes you need to delete the cookies from selected sites or from a single site to clear specific preferences without deleting all Browser Cookies. You can do this through a little workaround with Firefox Options or by using Remove Cookies for Site addon for Firefox.
Remove Cookies for Site is a very simple Firefox addon that lets you delete all the cookies of currently opened website. Upon its installation, a “remove cookies for this site” option is added to the context menu in Firefox. The status of the operation of clearing cookies of selected sites is shown in the status bar. Like if you use this on the tab with Facebook open in it, all your login details and preferences for Facebook including the chat history will be deleted.
Deleting Cookies for selected sites from Mozilla Firefox security options is quick and easy.
On Mozilla Firefox, go to Tools > Options. Now under the “Privacy” tab, you will find a dropdown next to “Firefox will”. Choose the option, “Use custom settings for history”. Now click on Show Cookies button that appears on selecting the custom settings option. You will see a search box in the dialog box that appears. Type the name of the site for which you want the cookies to be deleted. For example, type “yahoo” and all the cookies from Facebook will appear. Select all of them(click on the first and then press Shift+Ctrl+End) and press Delete. This will simply delete all the cookies for Yahoo.