Examine source code of UsableHomeButton

{
  "manifest_version": 2,
  "name": "UsableHomeButton",
  "description": "__MSG_addon_description__",
  "version": "2.6",
  "author": "Marat Tanalin",
  "homepage_url": "__MSG_addon_url__",
  "default_locale": "en",
  "applications": {
    "gecko": {
      "id": "usablehomebutton@tanalin.com",
      "strict_min_version": "58.0"
    }
  },
  "background": {
    "scripts": [
      "/_/js/utils.js",
      "/_/js/options-utils.js",
      "/_/js/background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "/_/js/utils.js",
        "/_/js/content.js"
      ],
      "run_at": "document_end"
    }
  ],
  "options_ui": {
    "page": "options.htm",
    "browser_style": false
  },
  "browser_action": {
    "default_icon": "/_/i/button/enabled.png",
    "default_popup": "menu.htm"
  },
  "commands": {
    "site-home": {
      "suggested_key": {
        "default": "Alt+H"
      },
      "description": "Load home page of current site in active tab"
    }
  },
  "permissions": [
    "<all_urls>",
    "activeTab",
    "browsingData",
    "browserSettings",
    "clipboardWrite",
    "notifications",
    "history",
    "menus",
    "storage",
    "tabs"
  ]
}