This business of stressing over charging overnight has become an overblown issue.
I had an iPhone 5c for as long as I can remember and charged it every night the entire time I owned it...several years. When it did finally become time to retire it, retired i the battery was still holding a full charge every day. So, I honestly pay no attention to whether or not I charge all night.
Plus, I would dare say that most people who care one bit about whether or not it's safe to charge a phone battery all night are most likely the type who will actually update their phone way before the battery goes bad anyway.