Examine source code of Yomikiri

{
  "manifest_version": 2,
  "name": "Yomikiri",
  "version": "0.2.1",
  "description": "Look up definitions for Japanese words you encounter on the web. Add the word to Anki.",
  "author": "BlueGreenMagick",
  "icons": {
    "128": "res/assets/static/images/icon128.png"
  },
  "content_scripts": [
    {
      "all_frames": true,
      "js": [
        "res/content.js"
      ],
      "matches": [
        "http://*/*",
        "https://*/*",
        "file:///*"
      ],
      "match_about_blank": true,
      "run_at": "document_end"
    }
  ],
  "background": {
    "scripts": [
      "res/background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_icon": {
      "128": "res/assets/static/images/icon128.png"
    },
    "default_popup": "res/popup.html",
    "default_title": "Yomikiri"
  },
  "options_ui": {
    "page": "res/options.html",
    "open_in_tab": true
  },
  "permissions": [
    "storage"
  ],
  "optional_permissions": [],
  "content_security_policy": "script-src 'self' 'wasm-unsafe-eval'; object-src 'self'",
  "browser_specific_settings": {
    "gecko": {
      "id": "{65ce52a1-5b13-47f1-a7d9-fd5ae41e422c}"
    }
  }
}