<!DOCTYPE html> <html> <head> <title></title> <!-- This CSS will hit the non-optimised linear gradient painting path, since the dirty rect of div.inner will be the same as the destination rect, making cellContainsFill true in PaintGradient() and skipping the optimised path. --> <style type="text/css"> div.outer { border: 2px solid grey; padding: 0; height: 18.5px; width: 100px; } div.inner { margin: 0; padding: 0; border: 0; height: 18.5px; width: 100px; background: linear-gradient(to top, red, blue); } </style> </head> <body> <div class="outer"> <div class="inner"> </div> </div> </body> </html>