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.
if (this.value) {
      if (this.ui.imageEdit) {
        ui.children.push(this.value[$toHTML]().html);
      } else if (!this.ui.button) {
        const value = this.value.exData
          ? this.value.exData[$text]()
          : this.value[$toHTML]().html.value;
        if (value) {
          if (ui.children[0].name === "textarea") {
            ui.children[0].attributes.textContent = value;
          } else {
            ui.children[0].attributes.value = value;
          }
        }
      }
    }
    const caption = this.caption ? this.caption[$toHTML]().html : null;
    if (!caption) {
      
      ui.attributes.class.push("xfaLeft");
      return HTMLResult.success(createWrapper(this, html), bbox);
    }
    if (this.ui.button) {
      if (caption.name === "div") {
        caption.name = "span";
      }
      ui.children.push(caption);
      return HTMLResult.success(html, bbox);
    } else if (this.ui.checkButton) {
      caption.attributes.class[0] = "xfaCaptionForCheckButton";