Playing in Firefox

Firefox is not officially supported. The Olde World is only officially supported on the latest version of Google Chrome, where it is built and tested. Firefox uses its own rendering engine and can have trouble running the game: a low frame rate, stutter, or a game that doesn't start.

For the best experience, play in Google Chrome. Browsers built on Chrome, such as Microsoft Edge, Brave and Opera, are known to work okay. A downloadable client is coming soon.

If you'd rather stay in Firefox, the steps below can help. We can't promise the game runs well in Firefox even with all of them.

Fix 1: Turn on hardware acceleration

Without it, Firefox draws the game with your processor instead of your graphics card, and the frame rate collapses.

Open the menu (the three lines at the top right) and choose Settings.
Go to Tabs and browsing and scroll down to Performance. In Firefox 151 and older, Performance is under General.
Tick Use recommended performance settings. If it is already ticked, untick it and make sure Use hardware acceleration when available is ticked.
Close Firefox and open it again.

Can't find it? Type hardware into the search box at the top of Settings.

Fix 2: Uncap the frame rate

Firefox draws a page as often as your monitor refreshes. On Windows it follows your main display, so with a 144 Hz monitor beside a 60 Hz main one, the game is held to 60. When Firefox can't tell the rate, it uses 60.

To see the limit, type about:support into the address bar and find Target Frame Rate under Graphics. If it is lower than your monitor's refresh rate, set it yourself:

Type about:config into the address bar and press Enter.
Click Accept the Risk and Continue.
Search for layout.frame_rate.
Click the pencil button, type your monitor's refresh rate (such as 144), and click the tick to save it.
Close Firefox and open it again.

On Windows, making the faster monitor your main display fixes it too.

The default is -1, which follows your monitor. 0 takes the limit away completely, so Firefox draws as many frames as it can. Some players use it, but it is a testing mode: your processor and graphics card work flat out in every tab, a laptop runs hot and drains its battery, and on a Mac or on Linux the picture can tear.

To undo any of it, search for layout.frame_rate again, click its Reset button, and restart Firefox.

A game stuck at 30 on a 60 Hz screen is not this limit. It means each frame takes too long to draw, so Firefox waits for the next refresh. Fix 1 and the sections below are what help there.

Check that it worked

Type about:support into the address bar and scroll down to Graphics.

Compositing should say WebRender. If it says WebRender (Software), Firefox is still drawing with your processor. Your graphics card or its driver may be on Firefox's list of known problems: update the driver and Firefox, restart, and look again.
WebGL 2 Driver Renderer should name your graphics card. Microsoft Basic Render Driver or llvmpipe means it is drawing without one.
If you see AllowWebgl2:false, Firefox has turned WebGL 2 off on this computer, and the game can't start in it.
Target Frame Rate should match your monitor's refresh rate.

Laptops with two graphics chips

Many laptops have a slow chip that saves battery and a fast one for games, and Firefox may be on the slow one. On Windows, Firefox uses whichever chip Windows gives it:

Open Settings, then System, Display, Graphics.
Find Firefox in the list. If it isn't there, add it with Add desktop app (Browse on older versions of Windows).
Set its GPU preference to High performance.
Close Firefox and open it again.

On a Mac with an Intel processor and two graphics chips, open System Settings, then Battery, Options, and untick Automatic graphics switching.

Privacy browsers and settings

Tor Browser and Mullvad Browser turn WebGL 2 off, so the game can't run in them at all.
LibreWolf, and Firefox with privacy.resistFingerprinting turned on, hold every page to 60 frames a second, round the game's clock off, and lower the graphics limits it relies on, which can break it. LibreWolf also blocks WebGL until you allow it from the icon in the address bar.

If you use one of these, play the game in Chrome.

Other things to try

Update Firefox (menu, Help, About Firefox) and your graphics driver, then restart your computer.
Plug your laptop in. On battery, many laptops slow their graphics down.
Close other busy tabs, such as videos and other games.
Turn your add-ons off (menu, Add-ons and themes) to see whether one of them is slowing the game.
In about:config, tick Show only modified preferences and reset any of these that an old guide changed: gfx.display.max-frame-rate, gfx.display.frame-rate-divisor, layers.acceleration.disabled, gfx.webrender.software, webgl.disabled.

Don't test the game in Firefox's Troubleshoot Mode. It turns WebGL off, so the game can't run there.

Why Firefox can be slower

Firefox keeps no copy of the game's shaders between visits, so it builds them all again every time you play, and loading takes longer.
Each of the game's drawing calls costs Firefox more than it costs Chrome, and the game makes a great many of them every frame.
On a Mac, Firefox draws through Apple's old OpenGL, where Chrome uses Metal. Firefox 160 is due to move to Metal.

Still having trouble?

Play in Google Chrome, the one browser we support. If it happens in Chrome too, tell us in our Discord, and we'll take a look.