{module}: a '{event}' before-handler rejected; the action was cancelled.

Warnings reference › *.beforeReject:*

Identifier

*.beforeReject:*

Raised by

Shared across modules

Since

1.53.0

What happened

An asynchronous before-handler returned a promise and that promise rejected. The module waits for every deferred handler - a logging handler still runs alongside a vetoing one - and treats a rejection the same way it treats a throw: the action is cancelled and the reason is reported.

The fix

The rejection reason is attached to the console line. Resolve false to veto deliberately; resolve anything else to allow the action.

The smallest fix

gantt.on('beforeTaskEdit', async (e) => (await mayEdit(e.task)) !== false);

Reference

Covered in full at the API reference.