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.

const storage = this.annotationStorage;
    for (const element of this._getElementsByName(
      base.name,
       base.id
    )) {
      if (element.domElement) {
        element.domElement[key] = value;
      }
      storage.setValue(element.id, { [keyInStorage]: value });
    }
  }
  render() {
    const storage = this.annotationStorage;
    const id = this.data.id;
    this.container.className = "textWidgetAnnotation";
    let element = null;
    if (this.renderForms) {
      
      
      
      const storedData = storage.getValue(id, {
        value: this.data.fieldValue,
      });
      let textContent = storedData.formattedValue || storedData.value || "";
      const maxLen = storage.getValue(id, {
        charLimit: this.data.maxLen,
      }).charLimit;
      if (maxLen && textContent.length > maxLen) {
        textContent = textContent.slice(0, maxLen);
      }