Examine source code of Lingua Libre SignIt

{
  "manifest_version": 2,
  "name": "Lingua Libre SignIt",
  "version": "1.0.19",
  "author": "Antoine '0x010C' Lamielle, Hugo Lopez",
  "description": "SignIt translate a selected word into Sign Language videos.",
  "homepage_url": "https://lingualibre.org",
  "applications": {
    "gecko": {
      "id": "signit@lingualibre.fr"
    }
  },
  "icons": {
    "32": "icons/Lingualibre_SignIt-logo-no-text-square-32.png",
    "48": "icons/Lingualibre_SignIt-logo-no-text-square-48.png",
    "64": "icons/Lingualibre_SignIt-logo-no-text-square-64.png"
  },
  "permissions": [
    "activeTab",
    "contextMenus",
    "webRequest",
    "webRequestBlocking",
    "storage",
    "<all_urls>"
  ],
  "browser_action": {
    "default_icon": "icons/Lingualibre_SignIt-logo-no-text-square-32.png",
    "default_title": "Lingua Libre SignIt",
    "default_popup": "popup/popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "css": [
        "lib/oojs-ui-wikimediaui.min.css",
        "content_scripts/signit.css"
      ],
      "js": [
        "lib/browser-polyfill.min.js",
        "lib/jquery.min.js",
        "lib/banana-i18n.js",
        "lib/oojs.jquery.min.js",
        "lib/oojs-ui.min.js",
        "lib/oojs-ui-wikimediaui.min.js",
        "SignItVideosGallery.js",
        "SignItCoreContent.js",
        "content_scripts/signit.js"
      ]
    },
    {
      "matches": [
        "https://*.wikipedia.org/*"
      ],
      "css": [
        "lib/oojs-ui-wikimediaui.min.css",
        "content_scripts/wpintegration.css"
      ],
      "js": [
        "lib/browser-polyfill.min.js",
        "lib/jquery.min.js",
        "lib/banana-i18n.js",
        "lib/oojs.jquery.min.js",
        "lib/oojs-ui.min.js",
        "lib/oojs-ui-wikimediaui.min.js",
        "SignItVideosGallery.js",
        "content_scripts/wpintegration.js"
      ],
      "run_at": "document_end"
    }
  ],
  "background": {
    "scripts": [
      "lib/browser-polyfill.min.js",
      "lib/jquery.min.js",
      "lib/banana-i18n.js",
      "background-script.js"
    ]
  },
  "web_accessible_resources": [
    "icons/*"
  ],
  "commands": {
    "_execute_browser_action": {
      "suggested_key": {
        "default": "Ctrl+Shift+L"
      }
    }
  },
  "content_security_policy": "default-src 'self' data: https://lingualibre.org https://*.wikimedia.org https://*.wikipedia.org https://*.wiktionary.org; script-src 'self'; object-src 'self' https://commons.wikimedia.org; style-src 'self' 'unsafe-inline'; img-src 'self' data:"
}