Builder doesn't install

[EasternIndustries-IT]

Using Bench or app.json builder doesn't install or install correctly
using docker exec -it root /bin/bash in backend and bench get-app builder, bench install-app builder , bench migrate, restart docker only results in blank screen when going to ip:port/builder. If this method doesn't work why is it still in docs?

using the apps.json just completly fails when doing docker build