I can see owned gadgets below avatars in the forum but I can't find a way to edit them. For example I sold my Mavic 2 long time ago and it is still displayed. I also bought Action 2 recently but it is not in the list of my gadgets. Appreciate your suggestions.

You can't.
They are linked to your account.
New ones should pop up automatically if you register them under the exact same email address.

Sometimes logging out and back in will bump new devices to appear,  but Ive not seen the OA2 yet so it may be there isnt an icon for that.

Thank you guys for the answers.
But how can I remove broken/sold gadget? Or will they haunt me forever?

utkin Posted at 11-3 04:07
Thank you guys for the answers.
But how can I remove broken/sold gadget? Or will they haunt me forever?

Personally I like to have them but you can ask in the Service -> Forum issues section and a DJI person might do it for you.