Recently empathy has switched it's behavior for open links.
At some point it was that links pasted in the IM window where open with whatever program was associated to the mime type of the link's content type, so, for example if the link was pointing to a image it was open in eog, if the link was a webpage it was open in gedit (my default setting).
Now it opens everything in chrome even though it's not my default browser, I've checked everywhere and chrome is not set as default.
I'm thinking that it's a bug but wanted to ask before going to launchpad. It's happening the same to you?
Is there a way to force empathy to open everything in firefox as a workaround?