Examine source code of ChatGPT Side Threads

{
  "manifest_version": 2,
  "name": "ChatGPT Side Threads",
  "description": "Open side conversations inside ChatGPT without losing focus — branch off, explore ideas, then collapse back to the main chat.",
  "version": "1.1.1",
  "icons": {
    "16": "icon/16-side-threads-icon.png",
    "32": "icon/32-side-threads-icon.png",
    "48": "icon/48-side-threads-icon.png",
    "128": "icon/128-side-threads-icon.png"
  },
  "permissions": [
    "storage",
    "tabs"
  ],
  "web_accessible_resources": [
    "/disable-scroll.js",
    "/icon/favicon.svg",
    "/gif/select-text.gif",
    "/gif/write-message.gif",
    "/gif/collapse-thread.gif",
    "content-scripts/chatgpt.css"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "side-thread@side-thread.com",
      "strict_min_version": "109.0"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_title": "Default Popup Title",
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "http://localhost/*",
        "https://chatgpt.com/*"
      ],
      "run_at": "document_start",
      "js": [
        "content-scripts/always-visible.js"
      ],
      "world": "MAIN"
    },
    {
      "matches": [
        "https://chatgpt.com/*"
      ],
      "run_at": "document_start",
      "js": [
        "content-scripts/chatgpt.js"
      ]
    }
  ]
}