Hello,
I noticed that the "Properties" panel causes a significant slowdown when I want to manipulate keyframes with my Keystone extension. I tested with other third-party tools to verify that this was not due to the Keystone code, and the results are identical.
I recorded a demo where I run a stagger on 750 keyframes, and you can see that when the Properties panel is displayed, it takes three times longer to calculate the requested stagger than when it is not displayed:
Properties panel OFF -> 04:36
Properties panel ON -> 14:93
As can be seen in the video, it is worth noting that there is no need to completely close the panel to gain performance.