sorry, I'm still confused how to register at branchable. whether after receiving an email, can you directly enter the branchable site?

because there is a choice of sites and emails, I enter the opinioncr

I agree, and blogged about something similar a while ago:

https://joeyh.name/blog/entry/idea:_git_push_requests/

ikiwiki-hosting would be one place to implement this, it already has hooks that filter incoming pushes for wiki criteria. However, it would probably be better to implement something standalone and then ikiwiki-hosting could just use it.

I would go with $foo.source.branchable.com instead.

Could we get HSTS and redirects from http to https?

Adding the site to HSTS preloads and or https-everywhere would be good too.

We're using letsencrypt wildcard support -- but it only allows for a single level of domain name above the wildcard, so does not work for source.$foo.branchable.com.

Renaming them to source-$foo.branchable.com, with a redirect from the old domain seems like the best way.

Aha, the ikiwiki logout button is on the Preferences page. I think it would be a good idea to include a "Logout" link that just goes to the Preferences page (or a new logout page).

I note that Let's Encrypt now offers wildcard support, which could be a useful option for supporting TLS.

Are you aware of alternative ways to provide content in multiple languages?

Yes, as far as I know there's not been any improvements to the 'po' module.

Is this still the case?

It would be good to use letsencrypt for that, the difficulty is that they only allow renewing a limited number of certs per month, and doubling the number of domains would be problimatic.

There are ways to bundle multiple domain into a letsencrypt cert, and getting source.foo.branchable.com at the same time it gets foo.branchable.com is doable, but would add complexity.

It might be simpler to get rid of the "source." domain and move that to somewhere under the main domain. Where exactly to avoid conflicting with any page names? Probably not "/source" ...