An application I am currently working on uses the SWT tool-kit's Browser widget to display a Firefox/XULRunner browser. I would like to set custom user agent data in Firefox about:config preferences; how does one alter them when working with SWT browsers?
I don't really work with the SWT browser, but http://dev.eclipse.org/mhonarc/lists/platform-swt-dev/msg06747.html seems to indicate there at least used to be an about:config in the SWT browser. Did you try it? What happened?
Also the SWT browser should have a profile named "eclipse" by default (it seems it's located at C:\Documents and Settings\<user name>\Application Data\Mozilla\eclipse\, see mozilla support for more info about profiles.
You should be able to edit prefs.js in there to set your preferences.