Before spending time troubleshooting in-game problems, it’s worth confirming that your browser and graphics hardware are actually capable of running the ClassicUO Web Client. This page lists the supported browsers and provides a set of quick test links that check WebGL, WebAssembly, and overall browser speed — all of which the Web Client depends on.Documentation Index
Fetch the complete documentation index at: https://mintlify.com/ClassicUO/classicuo-web/llms.txt
Use this file to discover all available pages before exploring further.
Browser Support
Not all browsers are equal when it comes to WebAssembly performance and storage quota. Use the table below to choose the right browser before you start.| Browser | Status | Notes |
|---|---|---|
| Chrome | ✅ Recommended | Best overall compatibility and WebGL performance |
| Chrome (installed as app) | ✅ Recommended | Standalone window, no tab bar, persistent storage, fewer hotkey conflicts |
| Microsoft Edge | ✅ Supported | Same Chromium engine as Chrome; often grants a larger storage quota and is a great choice for a dedicated game browser |
| Brave | ❌ Not supported | Aggressive fingerprinting and storage restrictions break the Web Client |
| Firefox | ❌ Not supported | WebAssembly threading model differs; not compatible at this time |
| Safari | ❌ Not supported | Missing WebAssembly features required by the client |
| Incognito / Private mode | ❌ Incompatible | Storage is severely limited (often under 100 MB); game files cannot be downloaded |
Microsoft Edge is built on the same Chromium engine as Chrome, so all
chrome://flags tips in the performance guide have equivalents at edge://flags. Edge is an excellent choice if you want a dedicated browser for the game.Is WebGL Working?
The Web Client renders entirely through WebGL 2. Use these two pages to confirm your browser can run WebGL and that it is using your real GPU rather than a slow software fallback.Check for WebGL 2 support
Open the following URL in your browser:If you see a spinning, colourful cube, WebGL 2 is working correctly. If the page shows an error or a blank canvas, your browser does not have WebGL 2 enabled — revisit the performance troubleshooting guide to enable hardware acceleration.
GPU Benchmark Tests
These tests measure how quickly your GPU can process graphics workloads in the browser. They are optional but useful if you want a baseline before and after applying performance fixes.WebGPU Stress Test
Pushes your GPU hard to surface thermal and driver issues under load. Good for checking stability.
GPU Benchmark with FPS Graphs
Runs a rendered benchmark and plots live FPS graphs so you can compare performance across settings.