is bug? Optimization viewmode -> light complexity flickering, also particle light flickering

This seemed to have happened when I upgraded from 4.14 to 4.16.
When I go to optimization viewmode and view light complexity, this happens. This is probably not normal, right? Should I be worried?
I don’t seem to notice anything weird when I play.

Also, this might or might not be related, but since I’ve upgraded, this particle blue light has its light turned on and off sometimes whenever I move around the viewport,as seen in this video. when I play the game, the blue light doesn’t flicker, however it doesn’t show up at all.

How do I solve this problem?