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)

...this.documentInfo,
      baseURL: this.baseUrl,
      filesize: this._contentLength,
      filename: this._docFilename,
      metadata: this.metadata?.getRaw(),
      authors: this.metadata?.get("dc:creator"),
      numPages: this.pagesCount,
      URL: this.url,
    };
  },
  /**
   * A place to fetch data for telemetry after one page is rendered and the
   * viewer is idle.
   * @private
   */
  async _collectTelemetry(pdfDocument) {
    const markInfo = await this.pdfDocument.getMarkInfo();
    if (pdfDocument !== this.pdfDocument) {
      return; 
    }
    const tagged = markInfo?.Marked || false;
    this.externalServices.reportTelemetry({
      type: "tagged",
      tagged,
    });
  },
  /**
   * @private
   */
  async _initializeAutoPrint(pdfDocument, openActionPromise) {