Clicking start leads to "Application error: a client-side exception has occurred (see the browser console for more information)." apart from Safari, which serve

Clicking start leads to "Application error: a client-side exception has occurred (see the browser console for more information)." apart from Safari, which serves me up a frozen game. Console errors complain about "THREE.WebGLRenderer: A WebGL context could not be created. Reason: WebGL creation failed: * tryNativeGL (FEATURE_FAILURE_CGL_FBO) * Exhausted GL driver options. (FEATURE_FAILURE_WEBGL_EXHAUSTED_DRIVERS)" Any tips? Are there magical flags that should be set somewhere?