Contact form allows duplicate submission

Description

Clicking Send twice quickly submitted the form twice. Could not be reproduced on every attempt.

Steps to reproduce

1. Open https://demo-shop.example.com/contact
2. Fill in all fields
3. Double-click Send

Expected result

The button is disabled after the first click and only one message is sent.

Actual result

Two success banners appeared and two POST requests were made.

Evidence

Page URL: https://demo-shop.example.com/contact

Timestamp: Wed, 15 Jan 2025 10:01:52 GMT