The WEBGL_lose_context extension is part of the WebGL API and exposes functions to simulate losing and restoring a WebGLRenderingContext.

WebGL extensions are available using the WebGLRenderingContext.getExtension() method. For more information, see also Using Extensions in the WebGL tutorial.

WEBGL_lose_context.loseContext()

Simulates losing the context.

WEBGL_lose_context.restoreContext()

Simulates restoring the context.

With this extension, you can simulate the webglcontextlost and webglcontextrestored events:

const canvas = document.getElementById("canvas");
const gl = canvas.getContext("webgl");

canvas.addEventListener("webglcontextlost", (event) => {
  console.log(event);
});

gl.getExtension("WEBGL_lose_context").loseContext();

// WebGLContextEvent event with type "webglcontextlost" is logged.

• WebGLRenderingContext.isContextLost()
• Events: webglcontextlost, webglcontextrestored, webglcontextcreationerror