Redirect loop on Make when visiting wp-admin over HTTP without a user role

If a logged-in user attempts to visit /wp-admin over HTTP on some Make sites that they don’t have access to, they get stuck in a redirect loop.

It doesn’t affect all of the sites, though, and it doesn’t happen if they request it over HTTPS.

e..g, requesting redirects to and then fails.

I’m seeing it on /training, /docs, /core, and /meta, but not on /community. I didn’t test beyond that, though.