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.

static IGNORE_TYPES = new Set([
    "Line",
    "Square",
    "Circle",
    "PolyLine",
    "Polygon",
    "Ink",
  ]);
  constructor(parameters) {
    const { data } = parameters;
    const isRenderable =
      !PopupAnnotationElement.IGNORE_TYPES.has(data.parentType) &&
      !!(data.titleObj?.str || data.contentsObj?.str || data.richText?.str);
    super(parameters, { isRenderable });
  }
  render() {
    this.container.className = "popupAnnotation";
    const parentElements = this.layer.querySelectorAll(
      `[data-annotation-id="${this.data.parentId}"]`
    );
    if (parentElements.length === 0) {
      return this.container;
    }
    const popup = new PopupElement({