I'm having a similar issue. This works fine in IE, I get the issue in FireFox. I have a style called nodisplay defined as:
.nodisplay
{ display: none;}
When I put this class on the Div that contains the CE Editor, I get a text height of 0
<div class="nodisplay">
<CE:EDITOR id="Editor4" EditorWysiwygModeCss="../example.css" runat="server" Height="250" AutoConfigure="Simple"></CE:EDITOR><br>
</div>
If I put the display style on the tag directly, it works fine:
<div style="display: none;">
<CE:EDITOR id="Editor3" EditorWysiwygModeCss="../example.css" runat="server" Height="200" AutoConfigure="Simple"></CE:EDITOR><br>
</div>
Why can't I use a CSS style sheet??