Dual monitor full screen gaming

I’ve been running dual monitors for a few months now. Whenever I play league of legends my main has it full screen but my second monitor shows half of a web browser. If i have the web browser full screen on my secondary it moves it to the right 50% so i see half of it and then the left 50% is just blank with my background. I thought it was a problem with just having 2 different monitors so I now have 2 Asus Vh238h monitors, still the same problem.

Any ideas?