I use a single monitor AND a light theme for my IDE.

This might be a bit off topic, but Windows 98, and to a lesser extent Windows XP and 7, always evoke a sense of nostalgic simplicity for me. The OS felt stable (as in, unchanging) and seemed to stay out of the way.

Since Windows 8, but especially with Windows 10 and 11, it’s felt complicated, busy, and intrusive.

My understanding is that it’s just the large nozzle extension that’s made of niobium as it’s radiatively cooled - the upper part of the bell and the combustion chamber is cooled by pumping propellant between the walls, so it can just be made of steel.

This is what the Merlin Vacuum engine looks like without the nozzle extension (though this is 1C): Image

It’s possible that the ‘stubby’ engine is just this.