bug#42406: Mouse-wheel scrolling can be flickering

[martin rudalics]

> In view of the comments made by Eli, I made a shoot in the dark, and,
>  in window.c, commented out the occurrences of wset_update_mode_line
>  on lines 1850, 4011, 5630, 5819, 6079, as well as the respective line
>  after the three statements lines where "Bug#15957" is written. With
>  these (actually I have not testes which of these (out-commentings are
>  relevant) the problem has completely gone. I am aware that this is
>  not a real solution, but it shows that there is some room. Which are
>  the risks caused by these changes of the code?

Does the line number displayed in the mode line update correctly when
you do that and scroll the window?

martin