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.

GetElementsByNameSet.add(element);
    element.setAttribute("data-element-id", id);
    element.disabled = data.readOnly;
    this._setRequired(element, this.data.required);
    element.type = "checkbox";
    element.name = data.fieldName;
    if (value) {
      element.setAttribute("checked", true);
    }
    element.setAttribute("exportValue", data.exportValue);
    element.tabIndex = DEFAULT_TAB_INDEX;
    element.addEventListener("change", event => {
      const { name, checked } = event.target;
      for (const checkbox of this._getElementsByName(name,  id)) {
        const curChecked = checked && checkbox.exportValue === data.exportValue;
        if (checkbox.domElement) {
          checkbox.domElement.checked = curChecked;
        }
        storage.setValue(checkbox.id, { value: curChecked });
      }
      storage.setValue(id, { value: checked });
    });
    element.addEventListener("resetform", event => {
      const defaultValue = data.defaultFieldValue || "Off";
      event.target.checked = defaultValue === data.exportValue;
    });
    if (this.enableScripting && this.hasJSActions) {
      element.addEventListener("updatefromsandbox", jsEvent => {
        const actions = {
          value(event) {