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.
constructor(attributes) {
    super(TEMPLATE_NS_ID, "radial",  true);
    this.id = attributes.id || "";
    this.type = getStringOption(attributes.type, ["toEdge", "toCenter"]);
    this.use = attributes.use || "";
    this.usehref = attributes.usehref || "";
    this.color = null;
    this.extras = null;
  }
  [$toStyle](startColor) {
    startColor = startColor ? startColor[$toStyle]() : "#FFFFFF";
    const endColor = this.color ? this.color[$toStyle]() : "#000000";
    const colors =
      this.type === "toEdge"
        ? `${startColor},${endColor}`
        : `${endColor},${startColor}`;
    return `radial-gradient(circle to center, ${colors})`;
  }
}
class Reason extends StringObject {