And I'm wondering, if I can see the measured recovery heart rate in Garmin Connect
Unfortunately the Recovery HR value is not being saved in the Activity file, but if you do it in the way I wrote, it will be included in the file - do not stop the activity, rahter just mark a lap, wait two minutes (that's the period used for the automated Recovery HR detection), then stop and save.You'll then see the HR values in the HR graph of the given activity. Currently you can see it only in the Daily HR graph - zoom at the end of the graph, point the mouse cursor at the time 2 minutes past the end of the activity, and you get the Recovery HR. Deduce the HR at the end of the Activity, and you get the Recovery HR 2min drop as shown originally on the watch.
If you wish that the watch stores the Recovery info in the Activity file, for later review in Garmin Connect, without the necessity to take it manually, suggest it to Garmin: Submitting an Idea to Garmin. If nobody (or just a few people) does, then it is not very likely to happen.