ChatGPT Browser Outage June 19: Chrome Users Hit 404 Errors After Redirect to Unified Gateway Subdomain, Desktop App Unaffected

ChatGPT experienced intermittent browser-based outages beginning around 9am AEST on June 19, with Chrome redirecting users to 'chat.gateway.unified-74.api.openai.com/' and returning 404 errors; the desktop app and mobile apps continued operating normally while browser access was disrupted. OpenAI acknowledged issues affecting its FedRAMP environment and recommended clearing browser cache, with Downdetector showing no concurrent US-region spike despite Australian reports confirming the redirect behavior. The incident followed SSO login errors that hit some ChatGPT Enterprise workspaces on June 18, suggesting back-to-back platform instability across two consecutive days.