GTA 3 Browser on Firefox: WebAssembly, WebGL2, Storage and Performance Guide
Run GTA III in Firefox with WebAssembly, WebGL2, OPFS, fullscreen, pointer lock and FPS guidance.
Firefox can run WebAssembly games
Firefox supports WebAssembly and WebGL2 and can run re3 browser builds. The experience can differ from Chromium because storage, graphics drivers and fullscreen behavior are browser-specific.
WebGL2 and graphics drivers
If WebGL2 is unavailable, update Firefox and the GPU driver. Software rendering can help diagnose compatibility but is not a good target for a real-time 3D game.
Site storage and OPFS
Firefox storage quotas and persistence decisions can differ from Chrome. Keep enough free disk space and avoid automatic site-data deletion if you want the cached archive to remain available.
Pointer lock and fullscreen
Mouse capture and fullscreen require user interaction. Click the canvas for input and use Escape to release the cursor. If fullscreen exits, retry from the visible control.
FPS and power
The same engine-side FPS cap works regardless of browser. If Firefox uses more CPU on your device, lower the cap to 30 or 50 and compare frame time and heat.
When to switch browsers
If Firefox fails at a browser API stage while the same archive works in Chromium, switching browsers is a reasonable workaround. If both fail asset validation, focus on the game data instead.
Play GTA III in your browser
Launch the re3 WebAssembly runtime with OPFS caching, fullscreen play and FPS controls.
▶ Play GTA III