!DOCTYPE html>
<html >
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
<style>
#container {
width: 400px;
height: 400px;
display: table;
}
#cell {
display: table-cell;
vertical-align: middle;
}
#cell_bk {
display: table;
overflow-wrap: break-word;
table-layout: fixed;
width: 20px;
}
.scroll {
height: 30px;
overflow-y: auto;
}
</style>
</head>
<body>
<div >
<div >
<div class="scroll">
<p >
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</p>
</div>
</div>
</div>
</body>
</html>