Way too much code to display. There are real time requirements on several things that matter (motions, safety, etc.) and obviously display refresh is not one of them. Same goes for other low priority tasks like submit interpreters...
And some programs are way linger than 20000 lines, they have to be split into many program filrs.
Could this be solved in sone way by KUKA? Certainly, but it is a really low priority item since it is purely cosmetic. If you do not like flicker, wrap the code into one or more folds, or make file invisible and call it from another program.
Switch the view to showing less lines, don't know the english menu entry by mind. You will see less lines but the flickering will get better.
"Line spacing normal/small"
Narrowing the lines in the program can be a solution.
