Attach (recommended) or Link to PDF file here:
[test planning.pdf](https://github.com/mozilla/pdf.js/files/7305078/test.planning.pdf)

Configuration:
- Web browser and its version: Firefox 93
- Operating system and its version: Windows 10 21H2
- PDF.js version: The integrated version
- Is a browser extension: no

Steps to reproduce the problem:
1. In the example, all shape and the "Line" cell of the first cell have a comment
2. Mouse over a "Line" cell or a shape, nothing appear except on mouse over their border
3. It is too difficult to use
4. There is also a vertical orientation issue reported in bug #7631

What is the expected behavior? (add screenshot)
Comments are shown on mouse hover or mouse click inside a cell or a shape

What went wrong? (add screenshot)
Comments are not shown when mouse hover or clicking inside a cell or a shape, only on their border

![image](https://user-images.githubusercontent.com/7791600/136419088-e083e2a3-d376-4d8c-9e0b-ce9dd5b83923.png)



selectElement.tabIndex = DEFAULT_TAB_INDEX;
    selectElement.style.fontSize = `${fontSize}px`;
    if (!this.data.combo) {
      
      selectElement.size = this.data.options.length;
      if (this.data.multiSelect) {
        selectElement.multiple = true;
      }
    }
    selectElement.addEventListener("resetform", event => {
      const defaultValue = this.data.defaultFieldValue;
      for (const option of selectElement.options) {
        option.selected = option.value === defaultValue;
      }
    });
    
    for (const option of this.data.options) {
      const optionElement = document.createElement("option");
      optionElement.textContent = option.displayValue;
      optionElement.value = option.exportValue;
      if (this.data.combo) {
        optionElement.style.fontSize = fontSizeStyle;
      }
      if (this.data.fieldValue.includes(option.exportValue)) {
        optionElement.setAttribute("selected", true);
      }
      selectElement.appendChild(optionElement);
    }
    const getValue = (event, isExport) => {
      const name = isExport ? "value" : "textContent";