--- title: ui_extension_errored description: >- The `ui_extension_errored` event logs occurrences when an extension fails to render due to an uncaught exception in the extension code. source_url: html: >- https://shopify.dev/docs/api/web-pixels-api/standard-events/ui_extension_errored md: >- https://shopify.dev/docs/api/web-pixels-api/standard-events/ui_extension_errored.md api_name: web-pixels --- # ui\_​extension\_​errored The `ui_extension_errored` event logs occurrences when an extension fails to render due to an uncaught exception in the extension code. **Note:** This event is only available on checkout. #### Properties * **client​Id** **string** The client-side ID of the customer, provided by Shopify * **context** **Context** A snapshot of various read-only properties of the browser at the time of event * **data** **PixelEventsUiExtensionErroredData** * **id** **string** The ID of the customer event * **name** **string** The name of the customer event * **seq** **number** The sequence index number of the event. * **timestamp** **string** The timestamp of when the customer event occurred, in [ISO 8601](https://en.wikipedia.org/wiki/ISO_8601) format * **type** **EventType.Standard** ### Context A snapshot of various read-only properties of the browser at the time of event * document Snapshot of a subset of properties of the \`document\` object in the top frame of the browser ```ts WebPixelsDocument ``` * navigator Snapshot of a subset of properties of the \`navigator\` object in the top frame of the browser ```ts WebPixelsNavigator ``` * window Snapshot of a subset of properties of the \`window\` object in the top frame of the browser ```ts WebPixelsWindow ``` ### WebPixelsDocument A snapshot of a subset of properties of the \`document\` object in the top frame of the browser * characterSet Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Document), returns the character set being used by the document ```ts string ``` * location Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Document), returns the URI of the current document ```ts Location ``` * referrer Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Document), returns the URI of the page that linked to this page ```ts string ``` * title Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Document), returns the title of the current document ```ts string ``` ### Location A snapshot of a subset of properties of the \`location\` object in the top frame of the browser * hash Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Location), a string containing a \`'#'\` followed by the fragment identifier of the URL ```ts string ``` * host Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Location), a string containing the host, that is the hostname, a \`':'\`, and the port of the URL ```ts string ``` * hostname Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Location), a string containing the domain of the URL ```ts string ``` * href Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Location), a string containing the entire URL ```ts string ``` * origin Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Location), a string containing the canonical form of the origin of the specific location ```ts string ``` * pathname Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Location), a string containing an initial \`'/'\` followed by the path of the URL, not including the query string or fragment ```ts string ``` * port Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Location), a string containing the port number of the URL ```ts string ``` * protocol Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Location), a string containing the protocol scheme of the URL, including the final \`':'\` ```ts string ``` * search Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Location), a string containing a \`'?'\` followed by the parameters or "querystring" of the URL ```ts string ``` ### WebPixelsNavigator A snapshot of a subset of properties of the \`navigator\` object in the top frame of the browser * cookieEnabled Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Navigator), returns \`false\` if setting a cookie will be ignored and true otherwise ```ts boolean ``` * language Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Navigator), returns a string representing the preferred language of the user, usually the language of the browser UI. The \`null\` value is returned when this is unknown ```ts string ``` * languages Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Navigator), returns an array of strings representing the languages known to the user, by order of preference ```ts ReadonlyArray ``` * userAgent Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Navigator), returns the user agent string for the current browser ```ts string ``` ### WebPixelsWindow A snapshot of a subset of properties of the \`window\` object in the top frame of the browser * innerHeight Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Window), gets the height of the content area of the browser window including, if rendered, the horizontal scrollbar ```ts number ``` * innerWidth Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Window), gets the width of the content area of the browser window including, if rendered, the vertical scrollbar ```ts number ``` * location Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Window), the location, or current URL, of the window object ```ts Location ``` * origin Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Window), the global object's origin, serialized as a string ```ts string ``` * outerHeight Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Window), gets the height of the outside of the browser window ```ts number ``` * outerWidth Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Window), gets the width of the outside of the browser window ```ts number ``` * pageXOffset Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Window), an alias for window\.scrollX ```ts number ``` * pageYOffset Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Window), an alias for window\.scrollY ```ts number ``` * screen Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Screen), the interface representing a screen, usually the one on which the current window is being rendered ```ts Screen ``` * screenX Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Window), the horizontal distance from the left border of the user's browser viewport to the left side of the screen ```ts number ``` * screenY Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Window), the vertical distance from the top border of the user's browser viewport to the top side of the screen ```ts number ``` * scrollX Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Window), the number of pixels that the document has already been scrolled horizontally ```ts number ``` * scrollY Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Window), the number of pixels that the document has already been scrolled vertically ```ts number ``` ### Screen The interface representing a screen, usually the one on which the current window is being rendered * height Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Screen/height), the height of the screen ```ts number ``` * width Per \[MDN]\(https://developer.mozilla.org/en-US/docs/Web/API/Screen/width), the width of the screen ```ts number ``` ### PixelEventsUiExtensionErroredData * error An object that contains data about a UI Extension error that occurred. ```ts UiExtensionError ``` ### UiExtensionError An object that contains data about a UI Extension error that occurred. * apiVersion The API version used by the extension. ```ts string ``` * appId The unique identifier of the app that the extension belongs to. ```ts string ``` * appName The name of the app that the extension belongs to. ```ts string ``` * appVersion The version of the app that encountered the error. ```ts string ``` * extensionName The name of the extension that encountered the error. ```ts string ``` * extensionTarget The \[target]\(https://shopify.dev/docs/api/checkout-ui-extensions/latest/targets) of the extension, for example "purchase.checkout.delivery-address.render-after". ```ts string ``` * message The message associated with the error that occurred. ```ts string ``` * placementReference The \[placement reference]\(https://shopify.dev/docs/apps/build/checkout/test-checkout-ui-extensions#dynamic-targets) of the extension, only populated for dynamic targets. ```ts string | null ``` * trace The stack trace associated with the error that occurred. ```ts string ``` * type The type of error that occurred. ```ts UiExtensionErrorType ``` ### UiExtensionErrorType * ExtensionUsageError An error caused by incorrect usage of extension APIs or UI components. ```ts EXTENSION_USAGE_ERROR ``` ### EventType * AdvancedDom ```ts advanced-dom ``` * Custom ```ts custom ``` * Dom ```ts dom ``` * Meta ```ts meta ``` * Standard ```ts standard ``` ### Examples * #### Accessing Standard Events ##### App Pixel ```js import {register} from '@shopify/web-pixels-extension'; register(({analytics}) => { analytics.subscribe('ui_extension_errored', (event) => { // Example for accessing event data const {apiVersion, appId, appName, appVersion, trace} = event.data.error; const payload = { event_name: event.name, event_data: { apiVersion, appId, appName, appVersion, trace, }, }; // Example for sending event data to third party servers fetch('https://example.com/pixel', { method: 'POST', body: JSON.stringify(payload), keepalive: true, }); }); }); ``` ##### Custom Pixel ```js analytics.subscribe('ui_extension_errored', (event) => { // Example for accessing event data const {apiVersion, appId, appName, appVersion, trace} = event.data.error; const payload = { event_name: event.name, event_data: { apiVersion, appId, appName, appVersion, trace, }, }; // Example for sending event to third party servers fetch('https://example.com/pixel', { method: 'POST', body: JSON.stringify(payload), keepalive: true, }); }); ``` ***