Hello,
I just noticed a strange behavior,
In this 3D view if I have no element selected Rhino seems to have trouble rotating (or zooming) the view.
But if I have an element selected everything is smooth.
In both cases my processor does not run at more than 15%.
I also tried without success to activate or deactivate the option “Rotate view around Gumball”.
It is a simple file but it was created with Rhino 6 (or 7 I do not remember) and the VisualArq plugin which creates a lot of blocks.
I can send it to you but only in PM if necessary.
jmv