Unwanted add-ons in your Firefox will occupy unwanted space and might slow down your browser when you browse. When you are not using an add-on it is better to remove them. Here we will see how to remove the add-on.
Go to Tools -> Add-ons -> this will open a new tab. Click Extensions link and this will show the add-ons you have installed on your browser. Click Remove button corresponding to the add-on tab and this will remove the add-on. For certain add-ons you may have to restart your browser to get this removed fully.