Examine source code of Feedly Notifier

{
  "manifest_version": 2,
  "name": "Feedly Notifier",
  "description": "__MSG_ExtensionDescription__",
  "version": "2.29.1",
  "default_locale": "en",
  "permissions": [
    "storage",
    "tabs",
    "notifications",
    "webRequest",
    "*://*.feedly.com/"
  ],
  "optional_permissions": [
    "<all_urls>"
  ],
  "browser_action": {
    "default_icon": {
      "19": "/images/icon_inactive.png",
      "38": "/images/icon_inactive38.png"
    },
    "default_title": "Feedly Notifier",
    "default_popup": "popup.html"
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "sidebar_action": {
    "default_icon": {
      "19": "/images/icon.png",
      "38": "/images/icon38.png"
    },
    "default_title": "Feedly Notifier",
    "default_panel": "popup.html",
    "open_at_install": false
  },
  "background": {
    "scripts": [
      "scripts/browser-polyfill.min.js",
      "scripts/feedly.api.js",
      "scripts/core.js"
    ]
  },
  "icons": {
    "16": "/images/icon16.png",
    "48": "/images/icon48.png",
    "128": "/images/icon128.png"
  },
  "web_accessible_resources": [
    "/images/icon128.png"
  ],
  "applications": {
    "gecko": {
      "strict_min_version": "62.0",
      "id": "jid1-BOjn8b0IM7kH2w@jetpack"
    }
  },
  "homepage_url": "https://olsh.github.io/Feedly-Notifier/"
}