Form-O-Fill : Extract and use a URL GET parameter

fof-extract-param-from-url.js

var rules = [{
  // Go to https://www.amazon.com/s/ref=nb_sb_noss_2?url=search-alias%3Daps&field-keywords=rainbow+pony
  // URL parameters are: url=search-alias%3Daps&field-keywords=rainbow+pony
  "url": /www.amazon.com/,
  "name": "Demo : Extract parameters from URL",
  "fields": [{
    "selector": "input[name=field-keywords]",
    "value": function($element) {
      // Construct via this nice helper : https://developer.mozilla.org/de/docs/Web/API/URLSearchParams
      var params = new URLSearchParams(window.location.search);
      
      // Extract one of the parameters:
      var keywords = params.get("field-keywords");
      
      return keywords + " some other term just to show it works";
    }
  }]
}];