[Evolution] Switching to browser?

[Leonard Evens <len math northwestern edu>]

When reading my mail in evolution, I often click on a web link in the
message,  A tab is opened in my running browser in another window.  The
system switches me to the browser, but on another machine, I have
managed to avoid that switch.  I would like to set things up the  same
way on this machine but I can't figure out how to do it.  As things now
stand, I have to switch back to evolution each time to finish reading my
mail.

Can anyone help me?