The MX Keys Mini has a light on the caps lock button that stays on based on the duration that it was pressed down. For example, if you hold down the caps lock button for 5 seconds, then turn caps lock off, the light will stay on for at least 5 seconds, usually longer. This also happens for the opposite situation.

I typically use caps lock as a push-to-talk button when in calls since it is the least disruptive button on the keyboard, but because of this weird light bug I can't actually figure out if the caps lock is on or off after I held down the button for some amount of time.

Also, I wish that there was an option in the Logi Options+ app that didn't just disable the caps lock completely, but instead kept it as a usable button, only disabling its function as a caps lock so that it could be bound to some other function instead. It's a very comfortable button to use for push-to-talk when playing games for example.