title: Make 'matches' URL of a Chrome Content Script Configurable
body: <p>I'm looking for a way how to make Chrome Content Script match URL configurable.</p>
  
  <p>Usually the URL for the script is specified in <code>manifest.json</code> within <code>matches</code> array. I believe I can set it to <code>http://*/</code> or <code>https://*/</code> and check/filter the execution at the beginning of the script for the required URL, but I was wondering if there is a cleaner way how to do this.</p>
  
  <p>Is there a way how to run the script for the configured URL, without being run at all if the URL doesn't match?</p>
  
  <p>Thanks</p>