I would like to create a block consisting of multiple other blocks, combined with a layout or some other kind of wrapper html.
A typical example would be a footer with 4 columns containing a menu, some custom text, etc.
The entire thing should be configurable in the UI and then exportable to the CMI system.
Known solutions
I know that this is possible in Drupal 7 using renderkit + cfrblock. However this has not been ported to Drupal 8 (yet). I will get there eventually, but atm I would like to find out if another solution might already exist.
EDIT: On D8 there is blockgroup, but it does not really work for me.
Related issues
How to group multiple blocks into one big block I think this is for D7.
Thanks!