In a nutshell, I wasn’t able to login after the site update. I tried this on three wifi networks, with no joy. It turned out not to be related to the update; it’s just that, since I last logged in (many months ago, as I leave it logged in) I’ve since installed Cloudflare Warp, a proxy client that makes your internet connection faster, more secure and private.
So if you use Warp, or anything similar, or probably some VPNs, and you’re getting the above issue, this might be the reason. Momentarily disabling Warp, then logging in to Elektronauts, then switching Warp back on fixed the issue for me.
Hope this helps someone!