Examine source code of Auto Jimaku Subs

{
  "manifest_version": 3,
  "name": "Auto Jimaku Subs",
  "version": "1.4.0",
  "description": "Find, list, auto-sync, style, and control Japanese subtitles from Jimaku for anime videos you allow it on.",
  "permissions": [
    "storage",
    "menus",
    "scripting"
  ],
  "host_permissions": [
    "https://jimaku.cc/*",
    "https://graphql.anilist.co/*"
  ],
  "optional_host_permissions": [
    "*://*/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "auto-jimaku-subs@example.local",
      "data_collection_permissions": {
        "required": [
          "authenticationInfo",
          "websiteContent"
        ]
      }
    }
  },
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "action": {
    "default_title": "Open Auto Jimaku Subs panel",
    "default_icon": {
      "48": "icons/icon-48.png",
      "96": "icons/icon-96.png"
    }
  },
  "commands": {
    "open-auto-jimaku-panel": {
      "suggested_key": {
        "default": "Alt+J"
      },
      "description": "Toggle Auto Jimaku Subs panel"
    }
  }
}