Examine source code of Glitch App to Project

{
  "background": {
    "scripts": [
      "browser-polyfill.min.js",
      "background.js"
    ]
  },
  "name": "Glitch App to Project",
  "description": "Go from a Glitch app (projectname.glitch.me) to a project page on Glitch (glitch.com/~projectname)",
  "homepage_url": "https://app-to-project-extension.glitch.me",
  "icons": {
    "16": "icon-16.png",
    "48": "icon-48.png",
    "128": "icon-128.png"
  },
  "page_action": {
    "default_title": "Switch between editor/app view of a Glitch app",
    "default_icon": {
      "16": "icon-16.png",
      "48": "icon-48.png",
      "128": "icon-128.png"
    },
    "show_matches": [
      "https://*.glitch.me/*",
      "https://*.glitch.com/edit/*"
    ]
  },
  "permissions": [
    "tabs",
    "contextMenus",
    "declarativeContent",
    "https://*.glitch.me/*",
    "https://*.glitch.com/edit/*"
  ],
  "version": "0.4",
  "manifest_version": 2
}