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.

if (!this.data.quadPoints) {
      return null;
    }
    const quadrilaterals = [];
    const savedRect = this.data.rect;
    for (const quadPoint of this.data.quadPoints) {
      this.data.rect = [
        quadPoint[2].x,
        quadPoint[2].y,
        quadPoint[1].x,
        quadPoint[1].y,
      ];
      quadrilaterals.push(this._createContainer(ignoreBorder));
    }
    this.data.rect = savedRect;
    return quadrilaterals;
  }
  /**
   * Create a popup for the annotation's HTML element. This is used for
   * annotations that do not have a Popup entry in the dictionary, but
   * are of a type that works with popups (such as Highlight annotations).
   *
   * @private
   * @param {HTMLDivElement|HTMLImageElement|null} trigger
   * @param {Object} data
   * @memberof AnnotationElement
   */
  _createPopup(trigger, data) {