Alpine.js + Pico CSS: Displaying a Loading Indicator on the HTML Form Submit Button

form.html

<div x-data="{ inProgress: false }">
  <form x-on:submit="inProgress = true" ...>
    ...
    <button type="submit" x-bind:aria-busy="inProgress" x-text="inProgress ? 'Please wait...' : 'Generate'"></button>
  </form>
</div>