Attach (recommended) or Link to PDF file here:
[imm5710f(1).pdf](https://github.com/mozilla/pdf.js/files/6924738/imm5710f.1.pdf)

Configuration:
- Web browser and its version: Firefox nightly
- Operating system and its version: Debian

Steps to reproduce the problem:
1. Open the pdf on page 3 
2. See the 2 fields after `DÉTAILS DU TRAVAIL PRÉVU AU CANADA`

What went wrong? (add screenshot)
![image](https://user-images.githubusercontent.com/5641725/128031365-84b17d62-f805-43d1-9d05-e2b535efa3ef.png)

const availableSpace = node[$extra].availableSpace;
  const marginV = node.margin
    ? node.margin.topInset + node.margin.bottomInset
    : 0;
  const marginH = node.margin
    ? node.margin.leftInset + node.margin.rightInset
    : 0;
  switch (node.layout) {
    case "lr-tb":
    case "rl-tb":
      if (node[$extra].attempt === 0) {
        return {
          width: availableSpace.width - marginH - node[$extra].currentWidth,
          height: availableSpace.height - marginV - node[$extra].prevHeight,
        };
      }
      return {