I Fixed a Silent Bug in an Open Source Project - Here's What I Learned

The bug looked small. An email input in a footer. But it was completely broken.

I was exploring the wagtail/news-template codebase as part of my Google Summer of Code (GSoC) application. I found the newsletter signup in the footer. You could type your email. You could click "Sign up". Nothing happened.

Why it broke

The "Sign up" button was an <a> tag. It linked to an external URL. It had no connection to the input field.

The input also had no name attribute. In HTML, form fields without a name are never submitted. Even if a form existed, the value would be lost.

The fix

I wrapped the input and button in a <form> element. I set the action to the external signup URL. I used method="get" so the email becomes part of the URL as a query parameter.

I also added name="email" and required to the input.

<form action="{{ signup_url }}" method="get">
  <input type="email" name="email" required placeholder="Enter your email">
  <button type="submit">Sign up</button>
</form>

Three lines changed. The feature now works.

What I learned

Small bugs can break core features. This signup appeared on every page of the site. Every visitor who tried it got no result.

Reading HTML carefully matters. You don't always need to run code to spot a problem. The structure tells you what will happen.

Open source is a good place to practice this. Real codebases have real bugs. Fixing them teaches you more than tutorials.

If you are new to open source, start by reading templates and forms. Look for missing attributes. Look for buttons that don't submit. These bugs are common and easy to fix once you know what to look for.