Recovery Heart Rate is always zero

Recovery heart rate has been present in Garmin Edges since at least the Edge 800 as I have been using it. I have the "530" and it has it. The problem is, getting the information out of the Edge into a program. The only program I have found to do it is "Sportstracks", the PC version, but, it was discontinued about 4 years ago despite the fact, people had purchased lifetime licenses. Now it is online only. Sadly my copy has stopped working a few months ago after a computer rebuild and my licence will not renew now.

Till I discovered my 800 had it, I would just stop the timer, make a note of the time on an "elapsed time" data field which will keep running and also my heart rate, keep still for two minutes and then subtract the current heart rate from what it was at the point of stopping riding.

There is an alternative way and it is to use a Fit file reader and you will find the info somewhere in an saved activity fit file. Why Garmin has a feature that will not import data into Garmin Connect, I don't know, makes it pointless having it.

Usually when I finish my ride, I stop the timer, and sit down for just over 2 minutes which is the time it is based on, then I save my ride.

In, fact, just recalled, I have recently been using an online site to upload my rides to and it's "intervals.icu" and after unloading to Garmin Connect it shows also in " intervals.icu" but the timing for HRV is only for a minute and not for two minutes. I think a minute is what runners use.

Works well with my HRM Pro plus and my edge840. but maybe because the HRM can also sync directly via the Garmin Connect Mobile App after you have stopped the Activity on the edge?!

 Don't know if someone already wrote following here, but:
RHR is measured after 2 minutes after you stopped the activity. Basically it means you have to wait 2 minutes or more after stopping your activity before you save it. Easy as that.
Why? The device is noticing your heart rate at the moment you stop the timer, at the moment you click save, your edge just substracts you HR at the "stop" moment and now (or 2 minutes after stopping the activity) - that's you RHR. 

Once more:
Stop the activity, when you're done. Wait at least for 2 minutes. Then save the activity. That's how you get your RHR. 
Don't forget, to get the correct RHR you better rest in those 2 minutes.

OK, nevermind.
Edge doesnt have the RHR measurement.
Connect Web doesn't show the value for the activities recorded with edge 840, only the Connect app, and it's always 0. 
Activities I record with my Forerunner always have RHR value more then 0, and it's shown on both, Connect Web and App.

The bug is, that the new revamped app shows the value even there's none

Yes, I do that. But it is still always shown as zero in the app. And yes, I sit right next to the Edge, still wearing the HRM, for that period. It simply doesn't work (for me). 

Yet with my Fenix 5+, following the same procedure, the watch does show the RHR. However, the app doesn't even show a row for that metric for apps uploaded from the Fenix.

Seems like typically buggy software from Garmin. 

As I have mentioned, the Garmin Edge does do RHR, mine does, but Garmin Connect will not show it and many other programs will not show it.

Try using the online program that I suggested, it shows it from the Edges fit file, so that proves the Edge does store it.

Alternatively, get a Fit file reader and examine the file, you will find RHR tucked away in the file.

Too much hustle:)

But officially esge 840 does not support recovery heart rate. At least I couldn't find any mention of this feature anywhere in the official sources. 

So, the bug, is that the connect app shows 0. Connect App's bug, not Edge's