Diagnosing H&M Supplier Portal Connection Resets
H&M’s supplier and vendor portal is hosted on Google’s GCP with Cloudflare as the CDN layer. The portal uses TLS 1.3 with ECH for all authenticated sessions. When suppliers access the portal from macOS Safari on networks with SSL inspection, the ISP gateway resets the ECH-enabled ClientHello, causing the TLS handshake to fail.
Google Cloud Load Balancer’s TLS configuration supports TLS 1.2 fallback, but Cloudflare’s edge policy requires ECH for TLS 1.3 and only offers TLS 1.2 fallback when explicitly signaled by the client. ISP gateways that strip the TLS 1.2 signal cause Cloudflare to assume TLS 1.3-only support, which fails.
Browser Integrity Sync on GCP Infrastructure
H&M’s supplier portal uses browser integrity sync across GCP’s global load balancing infrastructure. When the TLS handshake is interrupted, the integrity sync fails, and GCP’s security layer blocks the supplier’s access, requiring re-authentication.
Fixing H&M Supplier Portal Connection Resets
Disabling QUIC in Chrome
Download Chrome → Settings → Advanced → System → disable Use QUIC protocol. Access H&M Supplier Portal in Chrome — with QUIC disabled, Chrome uses HTTP/2 over TCP, which ISP gateways handle reliably.
Using Firefox with TLS 1.2 Maximum
Download Firefox → navigate to about:config → security.tls.version.max → set to 3. Access H&M Supplier Portal in Firefox — TLS 1.2 does not require ECH, allowing the handshake to complete through ISP gateways that block ECH.
Using VPN with European Endpoints
H&M’s GCP infrastructure is optimized for European traffic. Use a VPN with endpoints in Stockholm, Copenhagen, or Amsterdam to route your traffic through European ISP infrastructure that supports TLS 1.3 with ECH.
Call to Action
Use the webs.ninja network lab to verify connectivity to H&M’s supplier portal endpoints. The diagnostic identifies whether the reset is caused by your ISP’s gateway, a Cloudflare edge node failure, or H&M’s GCP infrastructure, directing the fix to the correct layer.