When I upgraded to 4.17 I noticed when I went to edit my widgets, I wasn’t able to click what I wanted - it was picking things hidden in the background (with the eye ball) (my pop ups/alerts).
To fix this I had to use the new locks on the Hierarchy tool window, and then things went back to normal.
Not sure if this is by design or not, personally I think this new locking should affect visible widgets only, if I have widgets hidden with the eyeball, I’ve already chosen to exempt it from clicks