Offscreen Documents

offscreen

Low RiskCategory: System & PerformanceView Official Docs↗

Technical Context

Allows the extension to create hidden documents for running DOM-dependent operations in the background. This enables audio playback, canvas rendering, and other DOM operations without visible windows.

What This Means For You

The extension can do things that normally require a visible page, like playing audio or processing images, without opening a window you can see.

Related APIs

This permission enables access to these Chrome APIs:

chrome.offscreen

Common Use Cases

✓Audio players
✓Image processors
✓PDF generators

How to Declare in manifest.json

Add the "offscreen" permission to your extension manifest:

{
  "manifest_version": 3,
  "name": "My Extension",
  "permissions": [
    "offscreen"
  ]
}

Related Permissions

Storage

storage

This acts as a digital filing cabinet where the extension saves your personal settings and preferences. It ensures your custom configurations stay the same every time you open Chrome without slowing down your computer.

low

Unlimited Storage

unlimitedStorage

The extension can save more data on your computer than the usual limit allows. This is useful for tools that need to work offline or save lots of information locally.

low

Alarms

alarms

The extension can set timers to perform tasks at specific times or on a regular schedule. This allows features like periodic sync, reminders, or scheduled updates to work reliably.

low

Idle Detection

idle

The extension can tell if you are actively using your computer or have stepped away. This helps it avoid interrupting you or save resources when you are not at your desk.

low

Power Management

power

The extension can keep your screen awake and prevent your computer from going to sleep. This is helpful when watching videos or during presentations.

low