I have a class formatted like this:

public class MyClass
    extends MyAncestor
    implements Interface1, Interface2

Now, when I invoke the Import Management Tool to
clean up my imports (mainly remove unused and
"optimize" named imports vs. "wilcard" imports)
the formatting will be changed so that everything
will be on one line even if there are no changes
to the class itself or the interfaces.

Steps to reproduce:

create several imports (which will be
corrected/optimized by the Import Management Tool)
Format the class definition line with more than
one line
Execute the Import Management Tool