Is it just me or does the new Gmail UI feel sluggish/unresponsive? Scrolling the mail list is lagging a bit, the left side menu takes time to initiate the appear animation and the animation itself is too fast. When hovering the mouse over mail list, the interaction icons do the lagging effect, which is really not nice for eyes.

However the right side menu for Tasks, Calendar and etc. is nice, I like having them in one place instead of keeping multiple diff tabs open.

I'm not sure if this lag effect is intentional or a performance problem, maybe React instead of Angular could help :D