css - IE display: table-cell child ignores height: 100%

Question

I need to dynamically build a table to hold some data.
I've followed the usual approach of using divs with display: table, display: table-row and display: table-cell:

.tab {
    display: table;
    height:100%;
    width: 200px;
}

.row {
    height: 100%;
    display: table-row;
}

.elem {
    border: 1px solid black;
    vertical-align: top;
    display: table-cell;
    height:100%;
    background: blue;
}

.content {
    height: 100%;
    background: greenyellow;
}

<div class="tab">
    <div class="row">
        <div class="elem">
            <div class="content">
                Content
            </div>
        </div>
        <div class="elem">
            <div class="content">
                Longer content that will need to wrap around eventually you know and don't you hate it when things don't end as you expect them octopus
            </div>
        </div>
    </div>
</div>

Answer 1

Unfortunately, the effect of percentage values for height on display: table-row and display: table-cell elements is undefined according to the spec:

CSS 2.1 does not define how the height of table cells and table rows is calculated when their height is specified using percentage values.

So while a browser may claim to offer full support for table layout, certain aspects such as percentage heights may not be consistently implemented across all browsers because there is no correct behavior. You could try raising an issue on Microsoft Connect in hopes that they will change the behavior to be interoperable, but in the meantime you will need to find a different workaround (and even then you can't guarantee the behavior will remain interoperable, even in other browsers).

To make matters worse, I just tested and this affects all versions of IE up to and including 11, which means an IE-specific hack will fall short here. If you need to use a CSS table layout, as evidenced by the fact that you need to support IE8, then a pure CSS workaround is probably not feasible.