System crashes recently started
I have not had a system crash for years. Even apps freezing and having to be forced quite is a rarity. But lately, my system is crashing a few times a week. I will be working away, the screen will go dark as if the battery died (brand new battery with 45% this time when it crashed), then I get the sign in screen and all my apps reboot. I restarted in Recovery mode and ran the repair utility but it said everything was fine. Is anyone else having this problem or do you know why it is happening?
MacBook Air, macOS Sierra (10.12.6)