[Client] Game turns client into a sliver that shows a small portion of the end-game screen

This has happened on my PC and my laptop, in the most recent patch and the patch prior a week and a half or so back. On my pc I was playing windowed mode, and on my laptop it was in full screen. Since there's nothing else to click on for the client window I have to force quit the process. There was a yes or no option from the 'waiting for stats' dialogue in the sliver, and I was able to click no and see this portion of the post-game screen.

I alt-tabbed at a couple of points in the game, I wouldn't think it's related to the issue since people alt-tab all the time and I do it without issue most other times I play, but it's worth noting.

Could be related, but this other even happened on my laptop in the same session. For the game that the sliver bug happened in, I was able to complete champ select but was booted out by bug splat so my client could repair itself. Once the repair finished, I was in the game 5 minutes in. Hasn't happened to me before on my pc, with the same graphics settings.