STR:
  - Go to https://mozilla.github.io/pdf.js/web/viewer.html
  - Click on "Open File" and open a pdf

The `Download` button and the `Current view` one just disappear.
I can reproduce this bug with Firefox nightly, Chrome stable and Epiphany on debian.
const moreInfoText = [
      this.l10n.get("error_version_info", {
        version: version || "?",
        build: build || "?",
      }),
    ];
    if (moreInfo) {
      moreInfoText.push(
        this.l10n.get("error_message", { message: moreInfo.message })
      );
      if (moreInfo.stack) {
        moreInfoText.push(
          this.l10n.get("error_stack", { stack: moreInfo.stack })
        );
      } else {
        if (moreInfo.filename) {
          moreInfoText.push(
            this.l10n.get("error_file", { file: moreInfo.filename })
          );
        }
        if (moreInfo.lineNumber) {
          moreInfoText.push(
            this.l10n.get("error_line", { line: moreInfo.lineNumber })
          );
        }
      }
    }
    if (typeof PDFJSDev === "undefined" || !PDFJSDev.test("MOZCENTRAL")) {
      const errorWrapperConfig = this.appConfig.errorWrapper;
      const errorWrapper = errorWrapperConfig.container;