All the names and addresses in mass mailing , like us, are in the "To" field but is made invisible by an HTML code.

To make an element invisible, you can use the CSS visibility property. Here’s how you can apply it to hide the “To” field:

<style>
  .invisible {
    visibility: hidden;
  }
</style>

<input type="text" class="invisible" placeholder="To">

In this example, the .invisible class sets the visibility of the input field to hidden,