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)



element.textContent = textContent;
      } else {
        element = document.createElement("input");
        element.type = "text";
        element.setAttribute("value", textContent);
      }
      GetElementsByNameSet.add(element);
      element.disabled = this.data.readOnly;
      element.name = this.data.fieldName;
      element.tabIndex = DEFAULT_TAB_INDEX;
      elementData.userValue = textContent;
      element.setAttribute("id", id);
      element.addEventListener("input", event => {
        storage.setValue(id, { value: event.target.value });
        this.setPropertyOnSiblings(
          element,
          "value",
          event.target.value,
          "value"
        );
      });
      element.addEventListener("resetform", event => {
        const defaultValue = this.data.defaultFieldValue || "";
        element.value = elementData.userValue = defaultValue;
        delete elementData.formattedValue;
      });
      let blurListener = event => {
        if (elementData.formattedValue) {
          event.target.value = elementData.formattedValue;
        }