Designers who code would find this resource valuable because:

1. It solves a common UX problem: Textareas that automatically grow with content improve user experience and interface design.
2. The technique is clean and efficient, using minimal JavaScript and leveraging CSS for most of the functionality.
3. Understanding this approach helps designers think creatively about solving UI challenges using web technologies.
4. It demonstrates how to create custom form elements that enhance usability while maintaining a native look and feel.
5. The article provides insights into the nuances of working with form elements and text rendering in browsers.

The Cleanest Trick for Autogrowing Textareas: A Game-Changer for Web Forms

In the world of web design and development, creating intuitive and user-friendly forms is a constant challenge. One particular pain point has been the humble textarea - a crucial element for collecting longer text inputs, but one that often falls short in terms of user experience. Enter Chris Coyier's article on CSS-Tricks, which presents what might be the ultimate solution to this problem: a clean, efficient technique for creating autogrowing textareas.

Why This Matters

1. Improved User Experience: Autogrowing textareas eliminate the need for users to manually resize input fields, creating a more fluid and natural writing experience.

2. Clean Code: The solution presented is remarkably clean, requiring minimal JavaScript and leveraging the power of CSS. This approach aligns with modern web development best practices of keeping code lean and efficient.

3. Cross-browser Compatibility: The technique works across different browsers, ensuring a consistent experience for all users.

4. Performance: By using CSS for most of the heavy lifting, this method is likely to be more performant than JavaScript-heavy alternatives.

5. Accessibility: The approach maintains the native functionality of the textarea, which is crucial for accessibility.

The Clever Trick

The core of this technique lies in creating a hidden element that exactly replicates the content and styling of the textarea. This hidden element is allowed to grow naturally with its content, and through some CSS magic, it forces the visible textarea to match its size.

What makes this approach particularly elegant is its use of CSS Grid to overlay the elements, and a pseudo-element to hold the replicated content. This eliminates the need for additional DOM elements and keeps the markup clean.

Learning Opportunities

For designers who code, this article is a goldmine of insights:

1. It demonstrates creative problem-solving using standard web technologies.
2. It provides a deep dive into the behavior of form elements and text rendering in browsers.
3. It showcases how to create custom form elements that enhance usability while maintaining a native look and feel.
4. It offers a masterclass in attention to detail, explaining subtle nuances like the need for an extra space character to prevent "jumpy" behavior.

Conclusion

This CSS-Tricks article is more than just a tutorial for creating autogrowing textareas. It's a testament to the power of creative thinking in web development, and a reminder that sometimes the cleanest solutions are hiding in plain sight, waiting for someone to connect the dots. For any designer or developer looking to enhance their form design skills, this is an essential read and a technique worth mastering.

To implement the autogrowing textarea technique:

1. Create a container element for your textarea.
2. Add a textarea inside the container.
3. Style the container and textarea to match your design.
4. Add CSS to create a pseudo-element that replicates the textarea's content.
5. Use JavaScript to update the data-replicated-value attribute of the container when the textarea content changes.

Example HTML:

<div class="grow-wrap">
  <textarea onInput="this.parentNode.dataset.replicatedValue = this.value"></textarea>
</div>

Example CSS:

.grow-wrap {
  /* Easy way to plop the elements on top of each other and have them both sized based on the tallest one's height */
  display: grid;
}
.grow-wrap::after {
  /* Note the weird space! Needed to prevent jumpy behavior */
  content: attr(data-replicated-value) " ";
  white-space: pre-wrap;
  visibility: hidden;
}
.grow-wrap > textarea {
  /* You could leave this, but after a user resizes, then it ruins the auto sizing */
  resize: none;

  /* Firefox shows scrollbar on growth, you can hide like this. */
  overflow: hidden;
}
.grow-wrap > textarea,
.grow-wrap::after {
  /* Identical styling required!! */
  border: 1px solid black;
  padding: 0.5rem;
  font: inherit;

  /* Place on top of each other */
  grid-area: 1 / 1 / 2 / 2;
}