Editors often go to extremes in providing trivial facts to readers.
Literal
Editor [topic-は] trivial facts [object-を] readers [to-に] provide [for-のに] extreme [to-に] run [thing-こと] [subject-が] often exists.
極端に走る is an idiomatic expression meaning 'to go to extremes' — literally 'to run to the extreme.' The ~のに here means 'in the act of' providing. ~ことがよくある means 'it often happens that,' describing a recurring tendency rather than a single past event.