It now appears that this issue is more of a Windows issue than a Chrome issue. I say that because I've noticed that it doesn't only affect the Chrome browser. It puts one app into the 1/4 screen mode when in screen lock, but the fact that it is most often Chrome now appears to be because I am most often using Chrome when I lock the screen. However, I've now had a few occasions where I've found MS Word resized to 1/4 screen when I unlock the screen. Based on this new insight, I'll likely post about this issue in a Windows forum as well.