Examine source code of rename_tab_title

{
  "manifest_version": 2,
  "name": "Rename Tab Title",
  "version": "1.3.1",
  "description": "Rename tabs to know which account is in which tab. The custom name stays fixed while you navigate.",
  "browser_specific_settings": {
    "gecko": {
      "id": "tab-renamer@sudoahmed",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "permissions": [
    "tabs",
    "storage",
    "contextMenus",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_title": "Rename this tab",
    "default_popup": "popup/popup.html",
    "default_icon": {
      "16": "icons/icon-16.png",
      "32": "icons/icon-32.png",
      "48": "icons/icon-48.png",
      "96": "icons/icon-96.png"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_start",
      "all_frames": false
    }
  ],
  "commands": {
    "rename-tab": {
      "suggested_key": {
        "default": "Alt+Shift+R"
      },
      "description": "Rename current tab"
    }
  },
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  }
}