Problem with Firefox & IE8 not showing mouseover alt text for image maps

Question

I have the following HTML:

<div style="position: relative; text-align: left;">
<img id="chart_6c544b37_ac9d_49ed_912e_5ff8ad6c0181_BaseImage" src="chart.gif" width="460px" height="240px" usemap="#chart_6c544b37_ac9d_49ed_912e_5ff8ad6c0181" border="0">

<map name="chart_6c544b37_ac9d_49ed_912e_5ff8ad6c0181">
<area shape="poly" alt="Second Dot" coords="256,51,259,48,256,45,253,48"></area>
<area shape="poly" alt="First Dot" coords="183,51,186,48,183,45,180,48"></area>
</map>
</div>

The Alt texts ("First dot" and "second dot") show correctly as tooltips when I hover over the areas on the graph when using IE7, but they do not show when using Firefox or IE8.

Any ideas why?

The example can be seen here

Answer 1

The attribute alt is only displayed when the the image can not be loaded. Use the title attribute instead.