Examine source code of Tab Freezer

{
  "manifest_version": 2,
  "name": "Tab Freezer",
  "version": "1.3.2resigned1",
  "description": "Activate Tab Freezer to automatically close popups and advertising tabs which get past ad-blockers",
  "author": "lynk",
  "applications": {
    "gecko": {
      "id": "tabfreezer@lynk",
      "strict_min_version": "57.0"
    }
  },
  "icons": {
    "32": "icons/tabfreezer_icon_blue_32.png",
    "64": "icons/tabfreezer_icon_blue_64.png"
  },
  "permissions": [
    "tabs",
    "storage",
    "webNavigation",
    "contextMenus"
  ],
  "commands": {
    "freezer-override": {
      "suggested_key": {
        "default": "Ctrl+Space",
        "linux": "Ctrl+Space",
        "mac": "MacCtrl+Space"
      }
    }
  },
  "browser_action": {
    "browser_style": true,
    "default_area": "navbar",
    "default_icon": {
      "32": "icons/tabfreezer_icon_off.png",
      "64": "icons/tabfreezer_icon_off.png"
    },
    "default_title": "TURN ON Freezing"
  },
  "options_ui": {
    "page": "options/tabfreezer_options.html",
    "browser_style": true,
    "open_in_tab": false
  },
  "background": {
    "scripts": [
      "tabfreezer_bg.js"
    ]
  }
}