Examine source code of Crunchyroll Picture-in-Picture Enabler

{
  "update_url" : "https://clients2.google.com/service/update2/crx" ,
  "manifest_version" : 3 ,
  "name" : "Crunchyroll Picture-in-Picture Enabler",
  "version" : "1.0.0",
  "description" : "Re-enables native browser Picture-in-Picture on Crunchyroll and adds an Alt+P hotkey to toggle it.",
  "content_scripts" : [
    {
      "matches" : [
        "*://*.crunchyroll.com/*" ,
        "*://static.crunchyroll.com/*" 
      ],
      "all_frames" : true ,
      "run_at" : "document_start" ,
      "js" : [
        "content.js" 
      ]
    }
  ],
  "action" : {
    "default_popup" : "popup.html",
    "default_title" : "Crunchyroll PiP"
  },
  "icons" : {
    "16" : "icons/icon16.png",
    "48" : "icons/icon48.png",
    "128" : "icons/icon128.png"
  }
}