With cabal 3.4.1.0, `cabal build` does not build the assistant, even though
all dependencies are there. Even after `cabal configure -fAssistant`, it
silently skips installing the deps for the assistant and does not enable the
CPP for the flag. Same for webapp.

Earlier versions of cabal did not behave this way. Perhaps it is a cabal
bug?

I tried moving the build-depends out of the `if flag(Assistant)` section
to the main build-depends section. It was able to install all the build
depends, so it's not some dependency issue making it decide to turn off
that build flag. --[[Joey]]

> [[fixed|done]] by moving the dependencies into the main block. --[[Joey]]