I had the experience that on GNOME on OpenBSD strangely Firefox is started as default. This shoudl not be the case as Epiphany is the default. One way to set it is when you start “gconf-.editor” and browse to the section where you might alos find firefox:
and change it right away to “epiphany %s”. This is only a fix. I need to find out why this is set false. Maybe somebody thinks GNOME should have Firefox as default. I could not change the default behaviour when just setting it right in “Preferred Applications”.