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.

this.setPropertyOnSiblings(
          element,
          "value",
          event.target.value,
          "value"
        );
      });
      element.addEventListener("resetform", event => {
        const defaultValue = this.data.defaultFieldValue ?? "";
        element.value = elementData.userValue = defaultValue;
        elementData.formattedValue = null;
      });
      let blurListener = event => {
        const { formattedValue } = elementData;
        if (formattedValue !== null && formattedValue !== undefined) {
          event.target.value = formattedValue;
        }
        
        event.target.scrollLeft = 0;
      };
      if (this.enableScripting && this.hasJSActions) {
        element.addEventListener("focus", event => {
          if (elementData.userValue) {
            event.target.value = elementData.userValue;
          }
          elementData.valueOnFocus = event.target.value;
        });
        element.addEventListener("updatefromsandbox", jsEvent => {
          const actions = {
            value(event) {