I sometimes see the issue where the screen position jumps when you type or click to select, but it is occasional not continuous. This is on iPad.
Maybe related to this?
As an example, I just opened an existing draft about 60,000 characters long, scrolled to the middle, and clicked. The window scrolled by itself to the end of the content, and the keyboard came up with the cursor positioned there, not at the point way above where I had clicked.