I use the addon Get Mail to open Outlook Express (I prefer it to Thunderbird) from Firefox but it will only open in minimised mode, have others found this and is there a fix available.
I tried that and even tried changing the default to maximise but its still not opening up with a full window. I think its a firefox problem because if I open outlook express without frirefox running it opens fine.
Sorry my suggestion didn't work. But I'm not sure it is a Firefox issue.
I don't use OE as my default client, but use Outlook. But when I try either set as default, they both open in a 'Normal' window when using the Read Mail extension.
Try un-installing, rebooting, then re-installing this new version of the 'Get Mail' add-on to see if that makes a difference.