Hi, when scrolling using the down arrow key I saw occasionally screen corruptions. The patch below fixes this for me. BTW. the following little program helped me debugging this and might be useful for others with too fast machines. It hogs the CPU, so dillo redraws are much slower and easier to follow: int main(int argc, char **argv) { for (;;); } Cheers, Johannes diff --git a/dw/fltkviewport.cc b/dw/fltkviewport.cc --- a/dw/fltkviewport.cc +++ b/dw/fltkviewport.cc @@ -311,8 +311,11 @@ void FltkViewport::scroll (int dx, int d { int hdiff = vscrollbar->visible () ? SCROLLBAR_THICKNESS : 0; int vdiff = hscrollbar->visible () ? SCROLLBAR_THICKNESS : 0; - int oldScrollX = scrollX; - int oldScrollY = scrollY; + /* multiple calls to scroll can happen before a redraw occurs. + * scrollDX / scrollDY can therefore be non-zero here. + */ + int oldScrollX = scrollX - scrollDX; + int oldScrollY = scrollY - scrollDY; if (dx == 0 && dy == 0) { return;