Test a local extension inside Workfront

After aio app dev (command catalog in appbuilder-workfront → references/commands.md) you have a localhost URL. This makes Workfront load your local app instead of (or alongside) published ones — no deploy required.

1. extensionOverride (the key step)

In the browser, on your Workfront tab (*.workfront.com or *.workfront.adobe.com): DevTools → Application → Local Storage → add an entry:

• key: extensionOverride
• value: your dev URL, e.g. https://localhost:9080

Take the exact URL/port from the aio app dev output. Reload the layout-template page — your extension's buttons/widgets appear.

For custom-form widgets, the widget picker lists locally-active apps when the override is set (surfaced as extensionoverride=TRUE).

Deployed app, no publish? Extension Manager (Bring Your Own)

extensionOverride points Workfront at a local (localhost) build. To use a deployed app (its CDN URL) in an org without the prod publish + approval process, register it in Extension Manager: