This is an irksome issue that has been bothering me for years now, and I finally figured; I'm probably not the only one.
Imagine this: A dualscreen set-up, two chrome screens open. One on the first screen with a youtube/netflix/social media/etc, the other on the second screen for working.
I'm a webdeveloper so I cmd-tab a lot back and forth to my coding app. Each time I do so, when I get back to Chrome, the 'first' screen is activated, while I was working in the second. When I switch back to chrome it's a force of habit to refresh immediately, causing me to refresh the wrong screen each damn time.
This might sound like a non-issue, but I hope you can understand it's insanely infuriating. Why isn't Chrome just remembering the last active instance as the main window to activate when switching back to it?
Angry sidenote: Google is all about usability and having the experience central. Thing is, I don't really notice it at all in their apps like Maps on mobile, things like this in Chrome etc.