[Gameplay] Interaction with Loading Client causing 3 FPS In-Game

I have two monitors (one is my laptop), and I often look at various League websites while in the loading screen. One issue that I have is that if I click on my browser while in loading screen, my loading screen does not stay open full-screen on my second monitor, even though my browser is on my first monitor (laptop). I've tested this with 3 different monitors and it works the same on all of them (I was using Windows 10 every single time). The actual bug happens when I click my browser too early. When the loading screen is all black, right before the champion portraits begin to appear, I might click on my browser (hiding my loading screen). When I return to the loading screen by clicking on the icon in my taskbar, all the text that should be white is black (the champion/skin names, the ping, the version in the bottom left corner, etc.). When the game finishes loading in, I have 3-4 fps when I should be getting 60. In order to fix this issue, I have to restart client, sometimes with visual bugs affecting my background (this is on my end cause it only happened with one). If I don't load back in quickly, my team is prompted with remake and, obviously, they remake (I'd do the same thing). I am then tagged with LeaverBuster.

I could just stop using 3rd party applications whenever I am playing League, but that isn't preferable. I would appreciate it if you could look into this bug. I believe the easiest fix would be implementing a Borderless Windowed option in the League game client (I've tested the one implemented right now and the same thing happens). With a few changes to the Borderless Windowed option, you can make it so it is impossible to hide the client. If you don't understand what I'm saying, it's the borderless windowed option in Overwatch. Thank you for looking into this and reading all of it!