Comment 9 for bug 306610

I also saw same problem on Thunderbird 2.0.0.x. On Shredder (trunk), no item is chosen instead of "Variable width".

The problem is caused by processes like following:
1. The preferences dialog is loaded. The menulist only have few built-in items,
   "Variable width", "Fixed width", etc.
2. <preference> tries to choose the menu item for "Arial". But there is no
   <menuitem> for the font. So, <preference> does nothing.
3. <prefpane> fires "paneload" event and gComposePane.init() is called.
   The list of installed fonts are generated by gComposePane.populateFonts().

To fix this bug, we have to generate the list of fonts before <preference>'s choosing.