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)

if (
      typeof PDFJSDev === "undefined" ||
      PDFJSDev.test("!PRODUCTION || GENERIC")
    ) {
      if (
        !(
          this.container?.tagName.toUpperCase() === "DIV" &&
          this.viewer?.tagName.toUpperCase() === "DIV"
        )
      ) {
        throw new Error("Invalid `container` and/or `viewer` option.");
      }
      if (
        this.container.offsetParent &&
        getComputedStyle(this.container).position !== "absolute"
      ) {
        throw new Error("The `container` must be absolutely positioned.");
      }
    }
    this.eventBus = options.eventBus;
    this.linkService = options.linkService || new SimpleLinkService();
    this.downloadManager = options.downloadManager || null;
    this.findController = options.findController || null;
    this._scriptingManager = options.scriptingManager || null;
    this.removePageBorders = options.removePageBorders || false;
    this.textLayerMode = Number.isInteger(options.textLayerMode)
      ? options.textLayerMode
      : TextLayerMode.ENABLE;
    this.imageResourcesPath = options.imageResourcesPath || "";
    this.renderInteractiveForms = options.renderInteractiveForms !== false;