Examine source code of Shark Javascript Injector

{
  "manifest_version" : 2 ,
  "name" : "Javascript Injector",
  "version" : "1.0.2",
  "browser_specific_settings": {
    "gecko": {
      "id": "javascript-injector@arturrosa.pl",
      "strict_min_version": "59.0a1"
    }
  },
  "description" : "Evaluate Javascript code on pages at a given domain without being blocked by CSP. Create custom shortcuts with JS.",
  "icons" : {
    "48" : "icons/js-48.png",
    "128" : "icons/js-128.png"
  },
  "permissions" : [
    "storage" ,
    "<all_urls>" 
  ],
  "browser_action" : {
    "default_icon" : {
      "48" : "icons/js-48.png"
    },
    "default_title" : "Javascript Injector",
    "default_popup" : "dist/popup/index.html"
  },
  "background" : {
    "scripts" : [
      "dist/background/background.js" 
    ]
  }
}