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)

pdfPage,
           null,
          this.imageResourcesPath,
          this.renderInteractiveForms,
          this.l10n,
           null,
           null,
           null
        );
      }
      this._renderAnnotationLayer();
    }
    if (this.xfaLayerFactory) {
      if (!this.xfaLayer) {
        this.xfaLayer = this.xfaLayerFactory.createXfaLayerBuilder(
          div,
          pdfPage
        );
      }
      this._renderXfaLayer();
    }
    
    
    if (this.structTreeLayerFactory && this.textLayer && this.canvas) {
      
      
      this._onTextLayerRendered = event => {
        if (event.pageNumber !== this.id) {
          return;
        }