I couldn't find a Share button in the web interface so I used the app. View the activity, click Share button > Web Link and share with something. I shared with Gmail. Note that you don't actually have to send it. Just discard the email. Badge awarded. If the activity isn't public the app will ask you to make it public.
Note: I accidently used my son's account first if another almost identical post also is posted.
It doesn't work for me. Activity is set to public, I press share button - web link and share. I have tried sharing via mail, messanger, notepad. still no badge. I have tried via the app and via web, no badge.
nallus - Thank you for the post. It sounds like you're doing everything right. I'd like to look into this further for you - do we have your permission to view your Garmin account to look into what's happening with that badge?
Garmin - DK - Yes. Thank you.