Examine source code of Webfeed

{
  "name": "__MSG_appName__",
  "short_name": "__MSG_appShortName__",
  "description": "__MSG_appDescription__",
  "version": "0.0.17",
  "manifest_version": 2,
  "default_locale": "en",
  "icons": {
    "16": "images/feed.svg",
    "128": "images/feed.svg"
  },
  "background": {
    "scripts": [
      "scripts/background.js"
    ]
  },
  "sidebar_action": {
    "default_icon": "images/feed.svg",
    "default_title": "Feeds",
    "default_panel": "sidebar/feeds.html",
    "open_at_install": false
  },
  "permissions": [
    "storage",
    "webNavigation",
    "webRequest",
    "tabs",
    "webRequestBlocking",
    "<all_urls>"
  ],
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "run_at": "document_end",
      "js": [
        "content-combined.js"
      ]
    }
  ],
  "page_action": {
    "browser_style": true,
    "default_popup": "pages/popup.html",
    "default_icon": {
      "19": "images/webfeed-page-action.svg",
      "38": "images/webfeed-page-action.svg"
    },
    "default_title": "__MSG_browserActionTitle__"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{076e1316-6b33-415b-9e2f-7f3673ae1ab6}"
    }
  }
}