<!DOCTYPE HTML> <html class="reftest-wait"> <head> <meta charset="utf-8"> <title>Testcase for bug 1010538 - Dynamically change scroll-behavior</title> <style type="text/css"> html,body { color: black; background-color: white; font-size: 16px; padding: 0; margin: 0; } .a_box { position: relative; left: 0px; top: 0px; width: 20px; height: 20px; background: blue; } .another_box { position: relative; left: 2000px; top: 2000px; width: 20px; height: 20px; background: green; } .scroll_box { width: 150px; height: 150px; overflow: scroll; } #scroll_2 { scroll-behavior: auto; } #scroll_3 { scroll-behavior: smooth; } </style> </head> <body> <div id="scroll_1" class="scroll_box"> <div id="box1a" class="a_box"></div> <div id="box1b" class="another_box"></div> </div> <div id="scroll_2" class="scroll_box"> <div id="box2a" class="a_box"></div> <div id="box2b" class="another_box"></div> </div> <div id="scroll_3" class="scroll_box"> <div id="box3a" class="a_box"></div> <div id="box3b" class="another_box"></div> </div> <script> function doTest() { if (document.location.search != '?ref') { // Expect smooth scroll: document.getElementById("scroll_1").style.scrollBehavior = "smooth"; document.getElementById("scroll_1").scrollTo({left: 0, top: 0}); document.getElementById("scroll_2").style.scrollBehavior = "smooth"; document.getElementById("scroll_2").scrollTo({left: 0, top: 0}); // Expect instant scroll: document.getElementById("scroll_3").style.scrollBehavior = "auto"; document.getElementById("scroll_3").scrollTo({left: 0, top: 0}); } else { document.getElementById("scroll_1").scrollTo({left: 0, top: 0, behavior: "smooth"}); document.getElementById("scroll_2").scrollTo({left: 0, top: 0, behavior: "smooth"}); document.getElementById("scroll_3").scrollTo({left: 0, top: 0, behavior: "instant"}); } // Interrupt any smooth scrolling for (var i=1; i <= 3; i++) { document.getElementById("scroll_" + i).scrollTo(); } document.documentElement.removeAttribute("class"); } for (var i=1; i <= 3; i++) { document.getElementById("box" + i + "b") .scrollIntoView({block: "start", behavior: "instant"}); } window.addEventListener("MozReftestInvalidate", doTest); </script> </body> </html>