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.

constructor(parameters) {
    super(parameters, { isRenderable: parameters.renderForms });
  }
  render() {
    const storage = this.annotationStorage;
    const data = this.data;
    const id = data.id;
    let value = storage.getValue(id, {
      value: data.exportValue === data.fieldValue,
    }).value;
    if (typeof value === "string") {
      
      value = value !== "Off";
      storage.setValue(id, { value });
    }
    this.container.className = "buttonWidgetAnnotation checkBox";
    const element = document.createElement("input");