Seltsam auch, nur bei Xfce wird das "sugar-browse-activity 200+20170502-1" Paket installiert. Die anderen flavors sind davon verschont.
Eine Antwort kam recht schnell
Zur Info, wen es denn interessiert ....something wrong with dependencies is my guess.
sugar-browse-activity is best used within the Sugar desktop, which
is the sucrose package on Debian.
sugar-activity provided by python-sugar3 package does not work
very well outside the Sugar user interface shell; just tried it then
and huge traceback because python-carquinyol wasn't installed, but
that's a recommends for python-jarabe so my mistake.
python-carquinyol installed and the sugar-browse-activity starts up,
but without any window manager decorations (in wmaker), because it is
written to be used within the Sugar desktop, which is a fullscreen app
design without windows.
sugar-browse-activity does suggest python-jarabe for the user
interface shell; perhaps it should require or recommend instead.
upstream has some more details if you're interested, see
http://www.sugarlabs.org/
http://wiki.sugarlabs.org/go/Debian
not surprised forums didn't know, see also
https://wiki.debian.org/Sugar