Just found some lagging when scrolling content in Chrome/Safari, especially after a few scrolls, the web page will pause about 0.5s then leap to the target position, which is quite annoying. After a few google around and testing, the Better Touch Tool v0.9995 is found to be the culprit. After disable it, all browsing returns smooth.
But as I use customized three finger swipes frequently, the magicprefs is now the alternative choice for gesture customization, which seems no conflict problem. But the system three finger swipe gesture must be disabled first in the trackpad preference pane, then the magic preference will enable the available gestures.
Just encounter a Yosemite system-wide problem of missing right click menu, but ctrl+click still works, which might be related to WindowServer process. Only reboot can get the right click back. After rebooting more than 10 times, it seems to happen after drag & drop to secondary monitor by bluetooth mouse. Quite strange, not sure if it’s bluetooth problem or drag&drop problem. Revert to Better Touch Tool temporally. And BTT released 1.0 which seems no lagging problem now.