Version: 5.4.2 RC9
Steps needed to reproduce the problem: Compile something that gets one or more warnings/errors. The compiler window will pop-open; the Editor cursor will be moved to the position of the warning/error; and the cursor's line will be highlighted. This highlight will disappear when any 'typing' key is pressed.. except 'delete' key; the line remains highlighted. (Even 'backspace' clears the highlight).