Since I was having issues with my notifications not working while on PC, and then when I got off they started working again, I went hunting.
I have found the issue on Win 10 I was having. For anyone else having the same issue, notifications not showing up while in game/any game
I had When I’m playing a game set to On. Which meant that all browser notifications while in any game, would not appear.
To find the setting, just search for Focus Assist