Attach (recommended) or Link to PDF file [here:] Can't see how to attach a pdf here, but it is simple to create. Add a form object textbox to a pdf and make sure the option for "Multiline" is true.

Steps to reproduce the problem:
1.  Open a document with a Textbox that is set to Multiline.
2. Attempt to hit the Enter key to go to a new line.

What is the expected behavior? The cursor goes to a new line.

What went wrong? It does not go to a new line.

Link to a viewer: It can be reproduced on mozilla.github.io/pdf.js

I corrected the issue by altering the pdf.js file like this
element.addEventListener("keydown", event => { 
[...]
--} else if (event.key === "Enter") {
++ } else if (event.key === "Enter" && !this.data.multiLine) {

Our initial testing is coming through clean, and hopefully something like this code can be committed to the project in the future.

while (selectElement.length !== 0) {
              selectElement.remove(0);
            }
            storage.setValue(id, { value: null, items: [] });
          },
          insert(event) {
            const { index, displayValue, exportValue } = event.detail.insert;
            const selectChild = selectElement.children[index];
            const optionElement = document.createElement("option");
            optionElement.textContent = displayValue;
            optionElement.value = exportValue;
            if (selectChild) {
              selectChild.before(optionElement);
            } else {
              selectElement.append(optionElement);
            }
            storage.setValue(id, {
              value: getValue(event,  true),
              items: getItems(event),
            });
          },
          items(event) {