Okay, but how does it differ from the eyeball icon that is there? TBH, I was always a bit fuzzy on the difference between the eyeball and the monitor, since they seemed to do much the same thing.
(I see you’ve already addressed this: that functionality seems quite redundant, and not worth the screen space.)
(New icons for Blender 2.8 - #2544 by Mr_Flamey)
Having just messed with them: there’s a hella long delay for a particular mesh (with 1 modifier) when you turn the monitor icon back on in my simple scene. Zero delay with eyeball. It’s like a 2.5 second delay before the element returns to the display, long enough to make you think something went wrong and click it a bunch more times. Other meshes in the scene don’t suffer this effect though.
EDIT: what I’d really like is a toggle to conceal the UI representation of, especially, the Lights, without removing their effect. TMK all the light toggling switches remove the effect of the light, not just their 3dview icons.