Running the Game in "fulltab"

At spawnd, we’re all about delivering the smoothest, most immersive gaming experience possible. Something that feels as close as possible to playing on a console, but right in your browser.

To make that happen, we require all games on the platform to run in fulltab mode. That means your game should cover the entire visible area of the browser (the full viewport), not just a small embedded frame (which is Unity’s default behavior). This helps eliminate distractions and puts the game front and center, just the way players (and your game) deserve.

Here’s how to set this up in Unity:

Unity Build Settings

Target Platform:
• Set Platform to WebGL. • In Player Settings, go to Resolution and Presentation.
Resolution Settings:
• Set Default Canvas Width and Height to auto-scaling values by leaving them blank or setting them large enough to be overridden by CSS/JS. • Enable: Resize WebGL canvas to fit the browser window
Run in Fullscreen:
• Set WebGL Template to a custom template (see below). • You’ll need to automatically trigger fulltab mode once the game loads.

Custom WebGL Template

Create a custom WebGL template to force the canvas to fill the screen:

In your Unity project folder:
• Go to: Assets/WebGLTemplates/FullTab/ • If the folder doesn’t exist, create it. • Inside, create an index.html file.
Use this simplified HTML template:

<!DOCTYPE html>

<html>
<head>
    <meta charset="utf-8" />
    <title>{{{ PRODUCT_NAME }}}</title>
    <style>
        html, body {
            margin: 0;
            padding: 0;
            overflow: hidden;
            background: black;
            height: 100%;
        }

        #unity-canvas {
            width: 100vw;
            height: 100vh;
            display: block;
            background: #000;
        }
    </style>
</head>
<body>

    <canvas id="unity-canvas"></canvas>
    <script src="Build/{{{ LOADER_FILENAME }}}"></script>
    <script>
        createUnityInstance(document.querySelector("#unity-canvas"), {
            dataUrl: "Build/{{{ DATA_FILENAME }}}",
            frameworkUrl: "Build/{{{ FRAMEWORK_FILENAME }}}",
            codeUrl: "Build/{{{ CODE_FILENAME }}}",
            streamingAssetsUrl: "StreamingAssets",
            companyName: {{{ JSON.stringify(COMPANY_NAME) }}},
            productName: {{{ JSON.stringify(PRODUCT_NAME) }}},
            productVersion: {{{ JSON.stringify(PRODUCT_VERSION) }}},
        });
    </script>
</body>
</html>

Back in Unity, in Player Settings > WebGL > Resolution and Presentation, select this new FullTab template.

Final Checklist for spawnd Compliance

• Game canvas fills 100% of the browser viewport;
• No scrollbars or borders; • Game starts in fulltab mode or on first user action; • Runs without letterboxing or aspect distortion; • Supports desktop controls (keyboard/gamepad); • Optimized for fullscreen immersion (no overlays or UI conflicts);

Need Help?

If you get stuck or need help applying the template, contact Contact the spawnd Team. We’re here to help you make your game shine.