NSISRT_Initialize failed!

When running makensis inside a docker, with a pretty minimal linux installation, I get: NSISRT_Initialize failed!
I'm running opensuse tumbleweed with nsis from the repository: https://download.opensuse.org/reposi...SE_Tumbleweed/
When running makensis on my own PC it works fine.
I'm gussing I'm missing some dependencies, but I have no idea what.

Most likely something to do with iconv.