The Optimize Tab
Your experience runs in a browser, and browsers reward small, tidy builds with fast loading and smooth play. The Optimize tab is where you tune for that. It has two sections: Asset Optimization, which shrinks textures and audio and shows you where your triangle budget is going, and Migration Cleanup, which repairs the broken references and leftover components that come along when you bring a scene over from another platform.
🎯 Where to find it
Open the Creator Dashboard from the U3D menu → Creator Dashboard and click the Optimize tab. Two buttons at the top switch between Asset Optimization and Migration Cleanup.
Asset Optimization
Smaller builds, set in bulk instead of one asset at a time
Unity lets you set per-asset compression and quality overrides for WebGL, but doing that by hand across hundreds of textures and audio clips is nobody's favorite afternoon. These tools apply sensible WebGL settings in bulk, and because they're standard per-asset overrides, the build pipeline respects them exactly as set and you can still fine-tune any individual asset afterward in the Inspector.
💡 How small is small enough?
There's no size limit imposed on you, so the real limit is your visitors' devices. Phones are the tight case: they have far less memory to work with, and experiences under about 50MB load and run comfortably on them. Desktop browsers handle considerably more, scaling with the machine. If your audience is mostly on phones, treat 50MB as the number to design toward. If you're building for desktop and headsets, you have more room, though every megabyte is still time your visitor spends staring at a loading bar.
💡 When to run these
Any time is safe, but the natural moment is before you publish: import your content, build your scene, then run Optimize Textures and Optimize Audio before heading to the Publish tab. Check Mesh Audit whenever the frame rate dips and you suspect a model is heavier than it looks. Build size analysis tools are also in development for this section.
Migration Cleanup
A starting point that saves real time
When you bring a scene into the template from another platform, the visual work comes with you, but components from that platform's SDK arrive broken: missing scripts that fill the Console with errors, object references pointing at nothing, and Visual Scripting graphs full of node types that no longer exist. Migration Cleanup won't magically port another platform's behaviors, but it clears the wreckage safely and shows you exactly what needs rebuilding with U3D tools, which turns a wall of errors into a working checklist.
Start with See What Needs Fixing, at the top of the section. It only looks; it never edits your scene:
- Highlight issues in Scene view is a toggle that color-codes problem objects right in your Scene view: red for missing scripts, yellow for missing references, and blue for placeholders added by the cleanup tools. The highlight refreshes itself after each cleanup tool runs, so you can watch the problems disappear as you work.
- Scan and Select All Issues scans the loaded scenes, reports how many missing scripts, missing references, and placeholders it found, and selects every affected object in the Hierarchy so you can see the full scope at once.
💡 Every cleanup tool is reversible
Each tool below asks for confirmation before it runs, and every change can be undone with Ctrl+Z. Feel free to try a tool, look at the result, and step back if it wasn't what you wanted.
Missing Scripts Workflow
Missing scripts are the empty "Missing (Mono Script)" components left behind when a scene references code that isn't in this project. The workflow is three steps, with two extra tools for when you'd rather skip straight to removal:
Swaps every missing script reference for a placeholder component. The errors stop, and each placeholder stays on its object as a visible reminder of what was there.
Work through the placeholder objects and rebuild their behavior, whether that's re-adding your own scripts or reaching for the equivalent U3D tools.
When everything's rebuilt, this clears the placeholder components and your scene is clean.
If you already know the missing scripts are dead weight, two direct tools skip the placeholder step: Clean Missing Scripts from Scene removes them from every object in your loaded scenes, and Clean Missing Scripts from Prefabs does the same for every prefab in a folder you choose.
Missing References Workflow
A missing reference is quieter than a missing script: the component itself is fine, but one of its Inspector fields points at an object that no longer exists, so something silently doesn't work. The workflow mirrors the scripts one:
Detects broken object references in your components and adds a tracking placeholder to each affected object, so the invisible problem becomes a visible list.
Locates and selects every object carrying a reference placeholder, so you can walk through them and rewire each field to the right object.
Clears all the tracking placeholders once the rewiring is done.
Visual Scripting Cleanup
Some platforms build their creator logic on Unity Visual Scripting with their own proprietary node types. Bring one of those scenes over and every Script Machine and State Machine that used those nodes throws errors, because the node types don't exist here. These two tools clear the broken graphs without touching the objects they live on, so your GameObjects, models, and layout survive intact:
With the broken graphs gone, step three is yours: rebuild the logic using U3D components or fresh Visual Scripting graphs. Visual Scripting itself works fine in the template; it was only the other platform's proprietary nodes that had to go.