The second display using the wired connection lags in my case(tab s7). I want to use the second display using wired connection. Is there a way to do that?

When I select some portion using smart select in dex mode. It selects only a part of it. I found that if you of you disable the Taskbar(Autohide) then it works fine, but does not work properly when Taskbar is there.Can Any give a solution to it?