Thank you, Sir. But that way not work.
I set top & left of window instead and it look cool.
<div id="w" class="easyui-window" data-options="title:'Inline Window',inline:true,fit:true,modal:true" style="padding:10px; top:10px; left:10px;">
Full code
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Test Texbox Multiline Height 100%</title>
<link rel="stylesheet" type="text/css" href="https://www.jeasyui.com/easyui/themes/default/easyui.css">
<link rel="stylesheet" type="text/css" href="https://www.jeasyui.com/easyui/themes/icon.css">
<link rel="stylesheet" type="text/css" href="https://www.jeasyui.com/easyui/themes/color.css">
<link rel="stylesheet" type="text/css" href="https://www.jeasyui.com/easyui/demo/demo.css">
<script type="text/javascript" src="https://code.jquery.com/jquery-1.9.1.min.js"></script>
<script type="text/javascript" src="https://www.jeasyui.com/easyui/jquery.easyui.min.js"></script>
</head>
<body>
<div class="easyui-tabs" data-options="fit:true,pill:true" >
<div title="Main Tab 1" style="position: relative; padding:10px;">
<div class="easyui-tabs" data-options="fit:true,plain:true,tabPosition:'left'">
<div title="Sub Tab 1" style="padding:10px;">
<a href="javascript:void(0)" class="easyui-linkbutton" onclick="$('#w').window('open')">Open Inline Window</a>
<a href="javascript:void(0)" class="easyui-linkbutton" onclick="$('#w').window('close')">Close Inline Window</a>
</div>
<div title="Sub Tab 2" style="padding:10px;">
<a href="javascript:void(0)" class="easyui-linkbutton" onclick="$('#w').window('open')">Open Inline Window</a>
<a href="javascript:void(0)" class="easyui-linkbutton" onclick="$('#w').window('close')">Close Inline Window</a>
</div>
<div title="Sub Tab 3" style="padding:10px;">
<a href="javascript:void(0)" class="easyui-linkbutton" onclick="$('#w').window('open')">Open Inline Window</a>
<a href="javascript:void(0)" class="easyui-linkbutton" onclick="$('#w').window('close')">Close Inline Window</a>
</div>
</div>
<div id="w" class="easyui-window" data-options="title:'Inline Window',inline:true,fit:true,modal:true" style="padding:10px; top:10px; left:10px;">
This inline window use together by Sub Tab 1, 2, 3
</div>
</div>
<div title="Main Tab 2" style="padding:10px;">
</div>
</div>
</body>
</html>