xren - the Extended Rename project

The width and horizontal positions of the both DIVs at the sides and the height of the DIV at the bottom are specified in 'em'. All of these DIVs are position:fixed.

Use the text zoom tool to change the font size. You'll realize that Mozilla 1.0RC1 will not change the dimensions and positions that are specified in 'em' until you reach a certain threshold. That threshold changes according to no apparent rule. Mozilla recalculates the DIV's dimensions immediately, if you change the window size, even if that change is only one pixel.

Note that Mozilla perfectly recalculates all values if the DIVs are position:absolute. Also note, that the margins of this main content DIV, which are specified with 'em' as well, are always correctly calculated.

This page's source code, relevant parts:

    <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
            "http://www.w3.org/TR/html40/strict.dtd">
    ...
    <STYLE TYPE="text/css"><!--
        div.content {
            margin-left:12em; margin-right:12em;
            border:#0000FF dotted 1px;
            padding:2px;
        }

        div.nav {
            color:#FFFFFF; background-color:#626262;
            border:#FFFF00 dotted 1px;
        }

        div.primnav {
            position:fixed;
            left:2px; right:2px;
            bottom:0; height:2em;
        }

        div.secnav {
            position:fixed;
            top:30%; bottom:2em;
            width:10em; right:1em;
        }

        div.thirdnav {
            position:fixed;
            top:30%; bottom:20%;
            left:1em; width:10em;
        }
    //--></STYLE>

more text

This page: http://xren.sourceforge.net/_moztestcase/em0.shtml