I’m not that familiar with rooting Android devices.
I’ve been able to follow the outline in the wiki. Currently I have been able to boot into twrp and wiped both data, cache and system and then rebooted again into twrp. I’ve downloaded e-0.2-201812222301-nightly-starlte.zip onto /sdcard/.
When I try to install it ends with error 7 (see enclosed pic). Vendor image on the device is NOT compatible.
Model of S9 is SM-G960F/DS
Any help appreciated.