ℹ️ This guide applies specifically to to checkout UI extension test It does not apply to payment customization tests or delivery customization tests.
If your checkout UI extension test is not working as expected, you are not alone.
Most problems are caused by a small setup detail in the Shopify checkout editor. This guide helps you identify the most common issues and fix them so your test can display correctly and start collecting data.
When to use this
Follow this guide if:
Your checkout UI test is live but nothing appears in checkout page
Reason 1: You forgot to add the ABConvert block in the checkout editor
Your checkout UI test will not show unless an ABConvert checkout UI block is added to your checkout editor.
How to check
Go to Shopify settings
Click Checkout
Open the Checkout editor
Check if there's any Checkout UI test placeholder block
If you do not see any ABConvert block, the test cannot render.
How to add ABConvert blocks
1. In the checkout editor, click + Add block
2. Select ABConvert > checkout-ui
3. Save your checkout configuration
Refresh your checkout page after saving.
Reason 2: The block ID does not match your test settings
Each ABConvert checkout UI block has a Block ID. Your test will only render in the block that matches the ID you set in the test.
If the IDs do not match, nothing will appear in checkout.
How to find your block ID
1. Open the Checkout editor
2. Find the ABConvert's Checkout UI test placeholder
3. In the block, you will see App Block ID: N
4. You can edit and assign a unique number on the left-hand side
How to use block ID in your test
Create a new checkout UI extension test in ABConvert
Find the Block ID field in the test settings
Enter the same block ID used in the checkout editor
Save and set the test live
For example, if your ABConvert block has App Block ID: 1, enter 1 in the test settings. The UI will then appear in that exact position in checkout.
Below it's how it will show up in the live checkout page:
Common mistakes to avoid
Any of these will prevent the checkout UI from showing:
Entering a block ID that does not exist in the checkout editor
Using the wrong block ID in the test settings
Changing the block ID in Shopify without updating the test
Reason 3: You added more than 3 app blocks in the same checkout section
Shopify allows a maximum of 3 app blocks in a row within the same checkout section.
This limit applies to:
ABConvert blocks
Other app blocks
Or a mix of both
If you exceed this limit, some blocks will not load.
How to fix
Open the Checkout editor
Locate the section with app blocks
Make sure no more than 3 app blocks are placed together
Remove or move extra blocks to another section
Click Save
FAQ
Q: Why is my checkout UI test live but nothing shows in checkout?
This usually means the ABConvert block is missing, the block ID does not match, or the app block limit has been exceeded.
Q: How many ABConvert checkout UI blocks can I use?
You can add multiple blocks, but Shopify only allows 3 app blocks in a row per checkout section.
Q: Do I need Shopify Plus to run checkout UI extension tests?
Yes. Shopify checkout UI extensions require Shopify Plus.