Firefox 'gets it right' IE inserts a p for each line break from the enter key, Firefox a br tag. You can use style in the head of the page to 'fix' IE, or just don't hit the enter key unless you want a new paragraph.
The 'fix':
Code:
<style type="text/css">
#oDiv p {
margin: 0;
}
</style>
Full demo:
Code:
<!DOCTYPE html>
<html>
<head>
<title></title>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<style type="text/css">
html, body {
height: 100%;
}
body {
overflow: hidden;
margin: 0px;
background-color: gray;
}
#oDiv {
height: 60%;
background-color: white;
overflow: auto;
width: 30%;
}
#oDiv p {
margin: 0;
}
</style>
</head>
<body>
<div id="oDiv" contenteditable></div>
</body>
</html>
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