Strange Rendering Problems in ViewPort

Alright, so i have started to face this problem from this version itself (v4.14) which is to see some strange rendering effects on main viewport. the effects include

  1. Strange lights coming from the border of editor’s main viewport
  2. Blurry Viewport
  3. Different Shading of game for Client and Server

Both of these occur frequently but the 1st one occurs after playing and the 2nd one on playing in viewport. One more thing i noticed is the problem only occurs in main window like not on those different windows which pops for client or when you play in an entirely different window.