---
title: "Reliable add to cart on Shopify's newest themes - Sign Customiser Changelog"
description: "Changelog: Reliable add to cart on Shopify's newest themes. Learn about the latest updates and improvements to Sign Customiser."
url: "https://www.signcustomiser.com/changelog/add-to-cart-fix-for-shopify-horizon-themes/"
last_updated: "2026-10-10"
---

Sign Customiser now adds custom signs to the cart correctly on Shopify’s newest theme family — Horizon and Vision, the successors to Dawn. Previously, when a shopper finished designing a sign on a store using one of these themes, the cart drawer wouldn’t open and the sign could be added twice, leaving customers with a doubled quantity and no confirmation that their design had been saved. Both issues are now resolved, so the add-to-cart experience is smooth and accurate across every supported theme.

## What’s Changed

- **Support for Shopify Horizon and Vision themes**Custom signs now add to the cart and slide open the cart drawer correctly on Shopify’s latest themes, giving shoppers instant confirmation that their design is saved.
- **No more doubled quantities**A custom sign is now added to the cart exactly once on every theme, so customers always see the correct quantity and price at checkout.
- **Fewer abandoned carts**With the cart drawer opening every time, shoppers are no longer left wondering whether their order went through, helping more designs make it to checkout.
- **Broader theme compatibility**We reworked how the cart refreshes across Dawn, custom-built, and other themes so the cart panel always updates reliably without re-adding the product.

- [fix](/changelog/tag/fix/)

Let your customers design their own signs

![Three custom sign types: neon, acrylic, and brushed metal letters](/_astro/sidebar-sign-showcase.9TDqJKD9_TbyVB.webp)

Add a full sign customiser to your online store in minutes. Neon, acrylic, metal — with real-time pricing.

[Start your free 7-day trial](/install/)

Works with Shopify, WooCommerce, Wix & more. 7 days free. Every plan includes every feature.

## Previousupdates

[View all updates](/changelog/)

- [May 5, 2026Show which characters a font can't renderThe customiser now lists the exact characters the chosen font doesn't support, and blocks orders with unsupported characters before they reach the merchant.feature](/changelog/show-unsupported-characters-in-sign-text/)
- [April 8, 2026Slim lightbox designs with recessed bordersCustomiser now officially supports single-sided (slim) lightbox designs with inactive side rendering, visible borders when sides are disabled, and optional recessed border styling.feature](/changelog/slim-lightbox-designs-with-recessed-borders/)
- [March 5, 2026Improved cut-to-shape backboard renderingCut-to-shape backboards now merge seamlessly with other backboards, wrap tighter around letters, and render with fewer visual artifacts for a true-to-life preview.fix](/changelog/improved-cut-to-shape-backboard-rendering/)
- [February 23, 2026Improved logo upload reliability and Safari compatibilityLogo-to-SVG conversions are now more reliable across all browsers, with significant improvements for Safari users.fix](/changelog/improved-logo-upload-reliability-and-safari-compatibility/)

[View all updates](/changelog/)

## Sitemap

See the full [sitemap](/sitemap.md) for all pages.