I don't think this is a new behavior (I think I reported it in some earlier pre cycles), but since it fits the GUI performance enhancements, here we go:
When clicking with the mouse on a fader and moving it, it stutters, gets laggy and even skips some movements (see gif). I grouped some faders to make the effect more obvious.
This does NOT happen, when an external device controls this fader (control surface) or
when, for example, using the fader from HeDa Track Inspector.
https://imgur.com/aUieSLu