Bug UI Scalling up the editor to 125% , scales down Game window

Unity release 2019.4.8 includes a dark interface. The font is not white and is light gray. I use a 4K monitor so after switching to dark mode since there is no custom font color or making the font bold, I need to scale up the UI Scaling to 125%. But in the Game tab, my game looks little and has a 25% margin around it. Is there some workaround?

Solution:

• Increase your contrast brightness or backlight of the monitor or TV.
• Before changing to 125%, close the Game tab. When you restart Unity, opening the Game tab should be fine