Hrvoje Niksic <hniksic(a)srce.hr&gt; writes: Why do you need the value as generated from the GUARANTEE=nil instead of GUARANTEE=t ? No it is not the lack of redisplay it is the lack of scrolling. Maybe that code is completely intertwined but it is conceptually different. Maybe the difference doesn't matter much, because you need to do part of the redisplay computation to know how to scroll. That may be necessary and then indeed it would do effectively the same as the window-end GUARANTEE code. I am not denying that window-start doesn't need fixing. I am just trying to explain why there is currently a difference between the two. Jan