How should a Shopify store audit the accessibility of its checkout extensions?
Checkout extensions need their own audit pass because they sit at the intersection of your code, the app's code, and the platform's constraints. Test each extension with a full keyboard run, a screen reader run, and deliberate error scenarios. Fix what you control, document what the platform controls, and re-audit after every extension update.
Why extensions need a separate audit
A theme audit does not cover checkout extensions. Extensions render inside the checkout's extensibility points with their own markup, their own focus behavior, and their own error handling, and they are often installed by apps whose developers never tested with assistive technology. The theme can be pristine while a loyalty-points extension traps every keyboard user who reaches it.
The risk is concentrated where it hurts most. Checkout is the highest-value flow on the store, and it is also where platform constraints limit what you can fix. That combination, high impact plus limited control, is exactly why extensions deserve dedicated audit time rather than being folded into a general pass.
Run the keyboard test first
Tab through the entire checkout with each extension active. Watch for the three classic failures: focus disappearing into the extension and never coming back, tab order jumping from the extension back to the top of the page, and interactive elements inside the extension that cannot be reached at all.
Test with the extension in every state it has: collapsed, expanded, error, and success. Extensions that behave in the default state often break in the error state, when an extra input or message appears that was never in the tab order plan. State changes are where focus bugs hide.
Run the screen reader test second
Listen to the extension with a screen reader the way a customer would. Every input needs a real label, not just a placeholder. Dynamic content, like a discount applied or points balance updated, needs to be announced through a live region, not silently changed. Status messages need to be reachable, not buried in markup the reader skips.
Pay attention to verbosity. Some extensions announce every internal state change, creating a wall of chatter that buries the information the shopper actually needs. Accessibility is not just about making things readable; it is about making the right things readable at the right time.
Test the error paths on purpose
Break the extension deliberately. Submit invalid input, trigger the failure states, disconnect whatever it depends on. Error handling is the most accessibility-sensitive part of any component: validation messages need to be associated with their fields, announced to screen readers, and must not move focus somewhere confusing.
Check recovery, not just the error itself. After an error is corrected, does focus return to a sensible place? Does the success state get announced? A surprising number of extensions handle the happy path accessibly and fall apart the moment something goes wrong.
Separate your findings from platform findings
Some findings will be in code you can change, and some will be in platform-rendered markup you cannot. Document the boundary for each finding: this label is ours to fix, this focus behavior is the platform's. The platform-side findings go into the same evidence log as everything else, with proof that the boundary was investigated.
This matters commercially as well as technically. When the store owner asks why a finding is still open after two sprints, the documented boundary turns a frustrating conversation into a factual one. It also protects the store if the issue ever appears in a complaint.
Re-audit on the extension's schedule, not yours
Extensions update on the app developer's schedule, and each update can reintroduce fixed issues or add new ones. Tie the re-audit to the extension's update events: whenever an extension version changes, the keyboard and screen reader passes run again on that extension's flows.
Keep the audit script so reruns are cheap. A written protocol, the same flows, the same checks, turns a two-day investigation into a two-hour regression pass. The stores with the best checkout accessibility are not the ones that audited once; they are the ones that made the audit repeatable.