UE editor menus lag

As I click on one of these top shelf menus, or main menu - “File, Edit, Window, Help”. Or the viewport’s icons “Perspectove | Lit…” etc. It opens only after 3-10 seconds! Or not opens at all sometimes.

The same issue in the content browser with a Right click on the folder or an item. If I click on the empty space menu opens immediately. Viewport not lagging itself, i can move there pretty fluently.

I have default project settings and props. I updated my Nvidia drivers.
I5-3.3Ghz x 4 ; 16gb ram ; 2tb HDD.

How to fix this lags??