Examine source code of MathPause – Mindful Website Blocker

{
  "manifest_version" : 2 ,
  "name" : "MathPause – Website Blocker & Math Challenges",
  "version" : "2.3.5",
  "description" : "Website blocker that helps reduce distractions by solving a math problem before accessing sites.",
  "permissions" : [
    "storage" ,
    "activeTab" ,
    "tabs" ,
    "*://*/*" 
  ],
  "icons" : {
    "16" : "icons/icon16.png",
    "32" : "icons/icon32.png",
    "48" : "icons/icon48.png",
    "96" : "icons/icon96.png"
  },
  "background" : {
    "scripts" : [
      "background.js" 
    ]
  },
  "browser_action" : {
    "default_title" : "MathPause",
    "default_popup" : "popup.html",
    "default_icon" : {
      "16" : "icons/icon16.png",
      "32" : "icons/icon32.png",
      "48" : "icons/icon48.png"
    }
  },
  "content_scripts" : [
    {
      "matches" : [
        "*://*/*" 
      ],
      "js" : [
        "content.js" 
      ]
    }
  ],
  "options_ui" : {
    "page": "options.html" ,
    "open_in_tab": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "mathmakecalm@addon-example",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    }
  }
}