Examine source code of Stop Russian Propaganda

{
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  "short_name": "__MSG_extName__",
  "version": "1.2.6",
  "description": "__MSG_extDescription__",
  "icons": {
    "16": "icons/icon16.png",
    "19": "icons/icon19.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "49": "icons/icon49.png",
    "128": "icons/icon128.png"
  },
  "default_locale": "uk",
  "browser_action": {
    "default_icon": "icons/icon19.png",
    "default_title": "__MSG_extDefaultTitle__",
    "default_popup": "popup.html"
  },
  "permissions": [
    "storage",
    "https://karatel.foss.org.ua/"
  ],
  "applications": {
    "gecko": {
      "id": "stop.russian.propaganda.ua@gmail.com",
      "strict_min_version": "57.0"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "css": [
        "css/styles.css"
      ],
      "js": [
        "js/lib/jquery-3.4.1.min.js",
        "js/lib/jalc.min.js",
        "js/lib/mark.min.js",
        "js/content.js"
      ]
    }
  ],
  "options_ui": {
    "page": "options.html"
  },
  "manifest_version": 2
}