Examine source code of Synced Lyrics Sidebar

{
  "manifest_version": 3,
  "name": "Synced Lyrics Sidebar",
  "version": "1.0.6",
  "description": "Displays synced lyrics in the side panel for the current playing song.",
  "icons": {
    "16": "icon.png",
    "48": "icon.png",
    "128": "icon.png"
  },
  "permissions": [
    "storage"
  ],
  "action": {
    "default_popup": "popup.html",
    "default_title": "Open Lyrics",
    "default_icon": {
      "16": "icon.png",
      "48": "icon.png",
      "128": "icon.png"
    }
  },
  "sidebar_action": {
    "default_panel": "sidepanel.html",
    "default_icon": "icon.png",
    "default_title": "Synced Lyrics"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "syncedlyrics@goseale.xyz",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_end"
    }
  ]
}