I was wondering if WebGL is considered stable enough to be enabled by default. It makes some PDFs render much faster and it has been off by default for a while now, so we have had quite some time to test it.

If we decide to enable WebGL by default, we should not forget to update https://github.com/mozilla/pdf.js/blob/master/extensions/chromium/preferences_schema.json#L39 as well.

/cc @yurydelendik 
/cc @Snuffleupagus (because IIRC you were testing WebGL too)

const worker = new Worker(workerSrc);
          const messageHandler = new MessageHandler("main", "worker", worker);
          const terminateEarly = () => {
            worker.removeEventListener("error", onWorkerError);
            messageHandler.destroy();
            worker.terminate();
            if (this.destroyed) {
              this._readyCapability.reject(new Error("Worker was destroyed"));
            } else {
              
              
              this._setupFakeWorker();
            }
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          const onWorkerError = () => {
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            if (data) {