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If you don't like the new features, it's easy to disable them: go to the "Options" menu from Google Calendar's navigation bar, select "Calendar settings", go to the "Event dimming" section and disable these two options: "Dim past events" and "Dim recurring future events".
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Google says that the brightness of these events is reduced "so you can focus on today", although you'll be able to better focus on the future, as well.
{ Thanks, Cougar. }