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)

constructor(pageIndex, pageInfo, transport, ownerDocument, pdfBug = false) {
    this._pageIndex = pageIndex;
    this._pageInfo = pageInfo;
    this._ownerDocument = ownerDocument;
    this._transport = transport;
    this._stats = pdfBug ? new StatTimer() : null;
    this._pdfBug = pdfBug;
    this.commonObjs = transport.commonObjs;
    this.objs = new PDFObjects();
    this.cleanupAfterRender = false;
    this.pendingCleanup = false;
    this._intentStates = new Map();
    this.destroyed = false;
  }
  /**
   * @type {number} Page number of the page. First page is 1.
   */
  get pageNumber() {