Regarding repaint view, go to about:config, nglayout.debug.paint_flashing to true, and you can catch some repaint problem. Agreed, it is not the most discoverab

Regarding repaint view, go to about:config, nglayout.debug.paint_flashing to true, and you can catch some repaint problem. Agreed, it is not the most discoverable feature. afaik, we don't have a tool for overdrawing. Hopefully this will change.