18.22 External HRM Connected, Green Lights on watch stay on

It was introduced  in some betas before. Like a feature. But now it is in public release  Can't understand  such a behavior. Battery drain and all the best - all the HR spikes that i saw before are smoothed out. Not usable at all for sprints/intervals. Very disappointing development.

I've got the same issue and I'm on fw 16.19, so, as global_local has said, it's apparently an old issue/feature, not related to this new firmware.

Very disappointing indeed.  I haven’t done any intervals yet, but that will upset me if it’s just a flat line.

I just had an online chat with support and the woman told me “It will always pull from the strap only. The lights are just design to stay on now just in case”. 

The last time I run I tried removing my watch from my wrist while the strap was connected and the watch sensor lights where on, and the watch continued to measure my hr correctly, so I think it's true that the watch still uses the band.

And why Garmin says, it is not a bug, but the new feature?

Nobody knows, we only know Garmin has said at least three times that this is not a bug, but an intended change.

Garmin also has said in this other post (referenced and cited by Garmin-Sierra in the post you sent) that it does this because it's necessary for a feature that will be introduced. So the sensor being on is not the feature, but something required in order to use the upcoming mistery feature.

Now speculating:

the only reason that I can think of for why they would activate the sensor, if the feature is not yet here, would be to collect data to compare the strap sensor data to the wrist sensor data.
That would be useful for features like the one that has just been released: <<Improved optical heart rate performance in cold weather.>>.

Another possibility, is to check if the watch is actually on your arm. That is used to decide if you need to enter the Garmin Pay PIN code again or not.

I doubt that's the case, because I don't use that feature.
It appears this issue has manifested itself in the past in the Garmin ecosystem and other people at the time came up with similar hyphothesis to the ones we just mentioned.
I don't know if that time the issue was fixed or not (someone would have to check if it is still happening on the Fenix 6) but this time Garmin has explicitly used the expression "Stay tuned", meaning something meaningful will come from this.

Same bug here since last update!

I see this topic was started 4 months ago but updated yesterday. is anyone still paying attention to this thread? If so I will join the discussion/