<!DOCTYPE html> <div style="writing-mode: vertical-rl;"> <div id="scrollable" style="width: 100px; overflow: hidden;"> <div style="height: 100px; width: 100px; background-color: silver;"></div> <div id="target" style="height: 100px; width: 100px; background-color: blue;"></div> </div> </div> <p id="result"> FAIL: Test did not run. </p> <script> if (window.testRunner) testRunner.dumpAsText(); var scrollable = document.getElementById("scrollable"); scrollable.scrollLeft = 40; var target = document.getElementById("target"); var hitContainer = document.caretRangeFromPoint(58, 100).startContainer; document.getElementById("result").innerText = hitContainer === target ? "PASS" : "FAIL"; </script>