I've been extremely busy this last week and something happened to my computer Friday. I didn't have time to look into what the problem was because I was sharing my screen and suddenly using Firefox or Vivaldi locked my screen up and just running one browser trying to share my screen took almost 4Gb of RAM and set my CPU around 75%+ usage.
Had to switch to another Laptop running Solus Gnome that had NOT been updated to share the screen.
Whatever happened seems to have went away but that is completely unlike my normal computing experience. It hasn't given me trouble since either.
Wish I had more input on what caused that.. hopefully I will be able to look into it today or tomorrow but there is a hurricane maybe possibly headed my way in South Florida so not sure. Don't know if this is related but maybe!