I have just upgraded from Nav 6.2.1 to 6.3.
There seems to be some buggy behaviour with the horizontal scrollbar in the Code Editor screen. The scroll bar either does not show or sometimes shows but does not let you scroll the entire width of the code.
I have attached an image to show an example where the code runs off the right hand side of the screen but no scroll bar is available to scroll and see it.
You can use the arrow keys to navigate to the end of the text but it is a pain.
I assume this is not a new preference setting as it would seem odd to have a preference to remove the scroll bar.