I don't use google so no data (of mine) to lose, and that did it.
I did manage to find the core problem, tho. Opening an image file did the same problem : ghost touch selected Default as I tapped Gallery. Of course, Gallery is right on the application list but again no default was set there or under Clear All... but I deleted the data and fixed it.
If It Is ( Google) Drive Pdf Viewer Then :-
Go To settings
App And Storage (Where You Can See Installed App Which Are Downloaded Or Pre Installed )
Select All Tab Where You Can See System Apps
Select Drive ( Triangle Logo With Three Colors Side Green, Yellow, Blue )
Scroll Down And Click On Clear Defaults ( If Not Available Directly Check Permission If ...