After the recent Launch changes to version control (which are very welcomed) it seems that the compare takes into consideration minor formatting changes as well so many times everything is highlighted as changed. I never saw this behavior before. Is this a known bug?
Every time you press "Save" in a Rule or Data Element, Launch saves a new revision of that asset. (You'll notice the revision number getting bumped with each "Save".) This behaviour has been there since day 1 of Launch, as far as I know. Version control gets its information from these revisions.
So if you're seeing minor formatting changes between revisions, it's most likely because you keep saving your rules/data elements.