I see the same behavior in 1.8.12. It works just fine.
It looks a little different, maybe, because my dpi is all messed up (so some text is the wrong size on this monitor) and I have “use external editor” enabled, which makes it grayed out.
This is the MPCNC_Ramps_T8_16T_LCD_32step_DualEndstop branch, from here: https://github.com/Allted/Marlin/tree/MPCNC_Ramps_T8_16T_LCD_32step_DualEndstop
So, what are we missing? What is different? What has changed?