Coupon Code Auto-Applier
Auto-apply best coupon at checkout.
shopping
PlugThis prompt
Build a Chrome extension called "Coupon Auto-Applier" that detects when the user is on a checkout page (common e-commerce platforms — Shopify, WooCommerce, BigCommerce). Fetch known coupon codes for the current domain from a bundled JSON list (and a user-editable allowlist), then try each code in the coupon field, watching for success/failure indicators in the DOM. Keep the best discount applied and surface a small banner showing how much was saved. Permissions: storage, activeTab. Host permissions: <all_urls>. Manifest V3 with content script.
How to build it in 3 minutes
- Sign in to PlugThis and open the chat input.
- Copy the prompt above and paste it into the chat.
- PlugThis generates the full Manifest V3 extension in 60-90 seconds.
- Download the zip, extract it, and load it via
chrome://extensionsdeveloper mode.