I am seeing something that I don't understand. There appears to be two threads on this problem, yet I only found one and posted to that one from the start. It had 17 pages and just turned 22 pages long. This thread seems to only have 6 pages, making me think it is a different thread. So, I will post what I just posted in what I believe is the other thread.
It has been two days since I tried the button sequence suggested by Steve Z. Have not had a single screen freeze on any of the 3 E4K units in our house since doing so yesterday morning. This may very well be the fix. It is not a full reset because it maintains your settings and icon selections. My guess is it turns off whatever feature is causing the screen freezes.
The fix is to push the following buttons the number of times listed in the order listed. Do it quickly.
Home - 5
Up - 1
Rewind - 2
Fast Forward - 2
Then wait. The menu will go a little crazy scrolling up and down and will eventually stop at Settings. Continue to wait. Eventually, the bouncing Roku logo will come up while the change takes place. When it is done, your home screen will come back up. So far, this has fixed the problem for me. But only time will tell.