Hi all,
good news for Pi Zero users:
The new image “Raspbian Jessie with PIXEL” comes bundled with the chromium browser. I’ve installed it tonight and chromium works on the Pi Zero (W). If I connect to a serveronly installation of MagicMirror the “ES6-problematic” modules (im my case: compliments, MMM-PublicTransportBerlin) comes up.

It’s not that fluently; CPU is 100% but it work’s.