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)

throw new Error("Not implemented: _viewerElement");
  }
  /**
   * @private
   */
  _onePageRenderedOrForceFetch() {
    
    
    
    
    
    
    
    
    if (
      !this.container.offsetParent ||
      this._getVisiblePages().views.length === 0
    ) {
      return Promise.resolve();
    }
    return this._onePageRenderedCapability.promise;
  }
  /**
   * @param pdfDocument {PDFDocument}
   */
  setDocument(pdfDocument) {