Crashes WebGL after a few renders

[bknill]

This is happening with this version and the previous, but after 2 or 3 renders WebGL crashes with this error:

THREE.WebGLRenderer.readRenderTargetPixels: readPixels from renderTarget failed. Framebuffer not complete.
GL_INVALID_OPERATION : glGenSyncTokenCHROMIUM: fence sync must be flushed before generating sync token
texImage2D @ three.min.js.jsf?ln=js:118
n @ three.min.js.jsf?ln=js:95
(anonymous) @ three.min.js.jsf?ln=js:177
Ae @ three.min.js.jsf?ln=js:7
Ga.upload @ three.min.js.jsf?ln=js:336
v @ three.min.js.jsf?ln=js:144
renderBufferDirect @ three.min.js.jsf?ln=js:162
r @ three.min.js.jsf?ln=js:131
render @ three.min.js.jsf?ln=js:175
render @ VREffect.js.jsf?ln=js:393
WebVRManager.render @ webvr-manager.js.jsf?ln=js:400
update @ SceneAdmin.js.jsf?ln=js:767
animate @ SceneAdmin.js.jsf?ln=js:754
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
requestAnimationFrame (async)
animate @ SceneAdmin.js.jsf?ln=js:753
edit:1 WebGL: CONTEXT_LOST_WEBGL: loseContext: context lost

I'm configured as such

	equiManaged = new CubemapToEquirectangular( renderer, false );
	cubeCamera = new THREE.CubeCamera( .1, 1000, 4096 );
	cubeCamera.position.copy( camera.position );
	cubeCamera.rotation.set(0,Math.PI/2,0);
	var options = { format: THREE.RGBAFormat, magFilter: THREE.LinearFilter, minFilter: THREE.LinearFilter };
	cubeCamera.renderTarget = new THREE.WebGLRenderTargetCube( 4096 , 4096 , options );


	interupted = true;
	cubeCamera.updateCubeMap( renderer, scene );
	equiManaged.setSize( 3840, 1920 );

	var data = equiManaged.convert( cubeCamera, false);
	processVideoImage(data);

Should I be clearing something out after each one?