Project Planner: Extend the Milestone Window

Can the overall milestone view in the Project Planner be extended to include special data?

In the Project Planner, there is an overview of all milestones at the project level:
Button “Edit Selection” → “Milestones” tab.

Here, existing milestones can be edited and new ones added.

Through customization, two additional columns can be displayed: a dropdown field and a checkbox.
The names of these fields and the dropdown options can be freely defined.
Example: Dropdown field “GATE TYPE” and checkbox “CAPEX”.

Below are the required technical settings for activating and configuring the fields:

In config.js

showMilestoneGateName: 'GATE-TYP'

showMilestoneCheckedName: 'CAPEX'

Optionally, a validation logic can be activated to define for which values in the dropdown field the checkbox should appear.
Currently, only one of the "checkable" fields can be selected at a time.

checkableMilestoneGates: ['A1','Gate 3','Gate 5']