Why an environment variable rather than a command line flag? Such variables are pretty undiscoverable.

In order to add a new command-line flag I'd need to rework the current naive flag handling.

I have no problem with this, but is that desired within the same PR?

Also, I followed something that seems to be a pattern (the only var exposed via a command-line flag is INSTALL_MODE). But I agree with the comment that:

Such variables are pretty undiscoverable.

@prusnak I think it's fine to do it as part of the same PR.

Added commit 9e12b2f which exposes installer config env vars via command line flags.

Review with -w / --ignore-all-space

Thanks!

FYI this doesn't seem to work in combination with --daemon, that's still updating a channel for me.

Weird, the code seems to be correct to me.