Attach (recommended) or Link to PDF file here:
PDF from #4106, https://mail.gnome.org/archives/evince-list/2013-November/pdfNC0hkVW67a.pdf.

Steps to reproduce the problem:
1. Open the PDF

What is the expected behavior?
![immagine](https://user-images.githubusercontent.com/1616846/121865567-67ca4200-ccfe-11eb-8673-1d6e863fc8d5.png)

What went wrong?
The PDF doesn't load, `TypeError: can't access property Symbol(), match is null` error is logged in the console.
const attributes = {
      style,
      id: this[$uid],
      class: classNames,
    };
    if (this.name) {
      attributes.xfaName = this.name;
    }
    const children = [];
    const html = {
      name: "div",
      attributes,
      children,
    };
    const borderStyle = this.border ? this.border[$toStyle]() : null;
    const bbox = computeBbox(this, html, availableSpace);
    const ui = this.ui ? this.ui[$toHTML]().html : null;
    if (!ui) {
      Object.assign(style, borderStyle);
      return HTMLResult.success(createWrapper(this, html), bbox);
    }
    if (!ui.attributes.style) {
      ui.attributes.style = Object.create(null);
    }
    if (this.ui.button) {
      Object.assign(ui.attributes.style, borderStyle);
    } else {
      Object.assign(style, borderStyle);
    }
    children.push(ui);