LAPLACE Chat

If your OBS contains multiple scenes — a light-background one for chit-chat, a dark-background one for gaming — the usual approach is to add two chat overlay sources in OBS, one set to light mode and one to dark. That has two drawbacks:

• It amounts to running two chat overlays in OBS, which costs extra resources, and even more once you have more than two scenes
• The overlay display is discontinuous and less smooth when you switch scenes

So the LAPLACE Chat overlay ships an original feature: it calls the OBS API directly, detects the scene type, and switches the overlay colors on its own

Usage

• In the browser source's Page Permissions setting, change the permission to Read access to user info (current scene collection, transitions)
• Right-click the chat overlay source and choose Copy
• Create a new scene or switch to another one, right-click the empty area of Sources, and choose Paste (Reference). Both scenes now show a chat overlay, but as pointers — they reference the same browser source
• Pick the scene whose overlay should go dark, right-click it, rename it, and add a [dark] marker to the scene name. It can go anywhere; the end is recommended, e.g. Fullscreen Game [dark]

If you would rather watch than read, follow the video tutorial below

Developers

As a developer, you can define [data-theme='dark'] and [data-theme='light'] to force either color scheme:

@layer template {
  [data-theme='light'] {
    --mix-base: #000;
    --mix-factor: 98%;
  }

  /* other styles */
  ...
}

Related Links

• Scene-based Styling (OBS) - Extend this approach to custom scenes so styles follow the scene
• Templates - Learn how template priority and cascade layers work