Attach (recommended) or Link to PDF file here:
http://education.ohio.gov/getattachment/Topics/Special-Education/Preschool-Special-Education/ETR-Preschool-Planning-Form.pdf.aspx

- Web browser and its version: Firefox 89.0.1
- Operating system and its version: Windows 10 10.0.19043.1052
- PDF.js version: commit 5d251a3a3e7bfaa8fbfa07f0b7f9901eb3f999d9
- Is a browser extension: No

Steps to reproduce the problem:
1. Enable XFA support
2. Open form

What is the expected behavior? (add screenshot)
Shapes stay inside table cells
![image](https://user-images.githubusercontent.com/7104454/122572782-1252a580-d01c-11eb-9d0f-5fed46d6f2fe.png)

What went wrong? (add screenshot)
Shapes fall outside cells (among other issues)
![image](https://user-images.githubusercontent.com/7104454/122572885-2d251a00-d01c-11eb-8863-fa3b9969f0ea.png)

}
    let marginH = 0;
    let marginV = 0;
    if (this.margin) {
      marginH = this.margin.leftInset + this.margin.rightInset;
      marginV = this.margin.topInset + this.margin.bottomInset;
    }
    const width = Math.max(this[$extra].width + marginH, this.w || 0);
    const height = Math.max(this[$extra].height + marginV, this.h || 0);
    const bbox = [this.x, this.y, width, height];
    if (this.w === "") {
      style.width = measureToString(width);
    }
    if (this.h === "") {
      style.height = measureToString(height);
    }
    const html = {
      name: "div",
      attributes,
      children,
    };
    const assist = this.assist ? this.assist[$toHTML]() : null;
    if (assist) {
      html.attributes.title = assist;
    }
    delete this[$extra];
    return HTMLResult.success(createWrapper(this, html), bbox);
  }
}
class Execute extends XFAObject {