All settings lost after upgrade to 2.1.0

What was the old version? 2.0 or 1.81?

I assumed that updating a plugin would deactivate and activate the plugin and calls the activation procedure. This procedure will convert the old to new values. But apparently it doesn’t deactivates/activates the plugin on update.

This was not testable before releasing. I will fix it in the next release, but for you and those already updated. You could deactivate and activate the plugin manually and all settings will old values will be copied.