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)

return (this._structTreePromise ||= this._transport.getStructTree(
      this._pageIndex
    ));
  }
  /**
   * Destroys the page object.
   * @private
   */
  _destroy() {
    this.destroyed = true;
    this._transport.pageCache[this._pageIndex] = null;
    const waitOn = [];
    for (const [intent, intentState] of this._intentStates) {
      this._abortOperatorList({
        intentState,
        reason: new Error("Page was destroyed."),
        force: true,
      });
      if (intent === "oplist") {
        
        continue;