(Normal Behavior) - Great watch, but issue #2: when heart rate strap attached and I choose "Run" in activities, the handheld heart rate green light is still on.

This is how Fenix 6 series behave in general, so it’s ”normal” behavior. If you want to be certain it’s using your HR belt, common suggestion is to use jacket power mode, which disables wrist HR completely.

It is an extra step + you miss heart rate tracking in time before exercise, but your suggestion fixes the uncertainty. Thanks 

great idea! Thanks

This is normal behavior. The OHR does not hand off to a heart rate strap until you start the activity.

Kurev said:

If you want to be certain it’s using your HR belt, common suggestion is to use jacket power mode, which disables wrist HR completely.

I believe (but maybe mistaken) that when the watch is using HR strap, the green lights on the back turn off, which is a quick way to check.

Also, personally I can immediately tell when my HR strap is working, just by seeing a far more stable HR reading on the watch. OHR tends to fluctuate +/- a couple BPM pretty rapidly, while HR strap tends to be a lot more smooth.

C.sco said:

I believe (but maybe mistaken) that when the watch is using HR strap, the green lights on the back turn off, which is a quick way to check.

This is correct, once you start the activity, you can quickly glance if lights are off. I do that often, it has become habit which I hardly notice anymore