How to make comments mandatory when manager bypass self-evaluation RW

Summary:

When a line manager click on "bypass self-evaluation", a tab on the left side opens (in redwood navigation).

On this tab, we need to have the comment mandatory to let the line manger doing the bypass

Content (please ensure you mask any confidential information):

As a manager, go to My Team > Performance, on the 3 dottes line, click on bypass self-evaluation, below the display:

How to make the box "add comments" mandatory ?

I have investigated through transaction design studio, but not action refers to this.

Through VBS, it is not possible to select the box individually, does someone have any idea how to perform this ?