Adds a custom attribute (url-url) to all body tags, to make it easier for CSS extensions to target specific URL's.
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Sometimes you want your CSS editor to only work on specific URL's within a domain, but it can't make its selections that specific. This script helps by adding a custom attribute, called "url-url", to the body tag of all web pages. This attribute contains the URL of the webpage, which allows your CSS to grab onto it.
