Any ideas about how to load some default widget in a custom sidebar on theme activation?

I have been searching on this for about 2 hours without any success and now it makes me crazy. :tired_face: :tired_face:

I’d like to achieve the same result like in twentyfifteen - if it’s activated from the wordpress admin - it inserts 5 widgets auromatically in the theme sidebar.

Any suggestions?
Cheers, Erik

change text-widget to the id of the other widgets