I can't display certain symbols on Firefox. Example: <span>&equiv;</span> does not show anything on the browser. However, <span>&rsaquo;</span> would show the correct symbol. I discovered a hack that displays the symbol by changing the tag. <h4>&equiv;</h4> will display the symbol. This hack, however is semantically incorrect and I don't want it in my site just so the symbol can display on Firefox. Any other suggestions?