<!DOCTYPE html> <style> #mc > div { position: absolute; inline-size: 50px; border: 10px solid; } </style> <p>Box shadows should not be painted at column breaks.</p> <div id="mc" style="position:relative; margin:50px; inline-size:400px; block-size:100px; background:yellow; writing-mode:vertical-rl;"> <div style="inset-inline-start:-10px; inset-block-start:-10px; block-size:100px; border-block-end:none;"></div> <div style="inset-inline-start: 140px; block-size:100px; border-block-start:none; border-block-end:none;"></div> <div style="inset-inline-start: 290px; block-size:50px; border-block-start:none;"></div> </div>