certbot-dns-azure 2.6.1 requires certbot<4.0; installing it into the image's certbot 5.x venv downgrades certbot and acme to 3.3.0, and acme 3.3.0 no longer imports against pyOpenSSL 26 (#5606). The maintained fork certbot-dns-azure-modern keeps module, entry point, flags and credentials format, requires certbot>=3.0 without an upper bound and declares its own azure-mgmt-dns range, so the extra dependency pin is no longer needed.