CRM delete button is missing in custom N:N subgrid

Hi

I'm currently having a problem with my CRM delete button is missing in custom N:N subgrid.
I found the information and it seems to point to a bug problem. How can I solve this problem?

Links:
community.dynamics.com/.../delete-button-is-missing-in-custom-n-n-subgrid
community.dynamics.com/.../delete-icon-not-shown-on-sub-grid
community.dynamics.com/.../821758

Peter

Thanks