Bryntum Support Forums

An error occurs when we're trying to remove a predecessor link using the undo functionality.

Steps to reproduce on the Advanced gantt example:

• Create 3 tasks A, B, C each connected through a Finish to Start Dependency
• Add 'A' as the predecessor of 'C' using the column (eg: 1;2)
• Hit 'Undo'

Uncaught (in promise) TypeError: Cannot set property from of [object Object] which has only a getter
    at Function.assign (<anonymous>)
    at UpdateAction.undo (gantt.module.js?466404:10:51

Attaching a video for your reference

Reproduced! Thank you for clear steps to reproduce. Here is the link to track the status https://github.com/bryntum/support/issues/6431