Examine source code of fei

{
  "manifest_version": 2,
  "name": "fei",
  "version": "1.0.6",
  "description": "Datensorglosigkeitsmessgerät",
  "icons": {
    "16": "icons/fei_logo.svg",
    "32": "icons/fei_logo.svg",
    "48": "icons/fei_logo.svg"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "data/strings.js",
        "data/functions.js",
        "data/fei.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "page_action": {
    "default_icon": "icons/fei_logo_false.svg",
    "default_title": "fei",
    "default_popup": "data/popup.html",
    "show_matches": [
      "<all_urls>"
    ]
  },
  "browser_action": {
    "default_icon": "icons/fei_logo_false.svg",
    "default_title": "dadendrang-fei"
  },
  "options_ui": {
    "browser_style": true,
    "page": "options/options.html"
  },
  "permissions": [
    "webRequest",
    "<all_urls>",
    "storage"
  ],
  "background": {
    "scripts": [
      "data/strings.js",
      "data/functions.js",
      "data/background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "fei.dadendrang.net@codecivil.de"
    }
  },
  "author": "codecivil",
  "homepage_url": "https://gitlab.com/codecivil/dadendrang-fei"
}