Came home from shopping today and Hubitat was nearly unresponsive. I say nearly because you could navigate to various apps, but it took several minutes for the app to fully load.
I had a blue light and 2 red advisory message 1) an update is available (I'm still on 188.8.131.52, and 2) Zigbee network is unreachable.
I felt comfortable that my recent backup would be adequate so skipped that step because the system was so slow.
I selected "shut down hub" from the Settings menu. It did that in a few minutes. Now I had a red light. I pulled the power cord and let the hub sit for 10 minutes. Applied power, everything seemed to start up normally, I have all my devices and rules, etc. I'm really happy and Hubitat is back to normal speed and Zigbee is online.
First time I had an issue like this and was really happy to get Hubitat up and running with little trouble and so quickly.