The game will not start, or displays badly

The game runs straight in your browser, with nothing to install. When it refuses to start, hangs while loading or shows a black screen, the cause is almost always the browser or the machine. Here are the checks, from the simplest to the rarest.

1. Reload, then clear the cache

Reload the page. If nothing changes, clear your browser's cache and cookies, then open the game again. That clears most loading problems, especially right after a game update.

2. Update your browser

A browser left without updates for a long time eventually cannot display the game any more. Install the latest version available, whichever browser you use, and restart it completely.

3. Try another browser

This is the quickest way to find out where the problem sits. If the game starts elsewhere, look at your usual browser rather than your machine. See Web browsers compatible with the game.

4. Turn your extensions off for a moment

Ad blockers, tracker blockers and security extensions sometimes stop the game from loading its data. Disable them for one attempt, or open the game in a private browsing window, where they are usually inactive.

5. Check that graphics acceleration is enabled

The game renders 3D inside the browser, and for that the browser needs to use your graphics card. In your browser settings, under System, graphics acceleration must be enabled. If you turned it off at some point, turn it back on: without it, recent browsers can no longer display the game at all.

Updating your graphics card drivers is worth doing too, outdated ones are a classic cause of black screens. See The black screen issue.

6. Check that your machine keeps up

The game needs a machine and a browser able to render 3D. See Minimum hardware requirements.

7. On a corporate or public network

Corporate networks, hotels and public hotspots often filter part of the traffic. The game may then open but stay incomplete, or drop mid-session. If you can, try another connection: that is the best way to tell whether filtering is to blame.

8. If the game closes abruptly

A message such as "Array buffer allocation failed" has its own cause and its own answer. See The web app crashes during play.

Nothing worked?

Write to us with your browser and its version, your operating system, and what you see on screen. A screenshot helps a lot. See Report a problem.

What about WebGL? That is the technology letting the browser display 3D. It is on by default in every up-to-date browser, so there is nothing for you to switch on. To understand what it does, see What is WebGL.