Switching belt - Underground - splitter when having either of them in hand

[erkki772]

I saw this elevated rails and saw that quick switch between building mode. It's really good question why we can't do that with belts too. This would free 2 building slot in building slot menu.

"I have this blue belt in my hand and want to do X position splitter" *start hovering to splitter to swap it*

With switching. *gently press G* twice.

Order would be: Belt - Underground - Splitter.

Extra: Swapping inserter would swap long handed. Quality match with current inserter.
Pipes would switch: Normal - Underground