Hi. Safari 26.1 breaks WebSockets in some cases, possibly on local network URLs when using TLS without a valid certificate.
Try using a valid TLS certificate — since the issue appears tied to Safari's treatment of WebSockets on HTTPS with self-signed certificates, installing a trusted cert (e.g. via Let's Encrypt with a local DNS name) often resolves it.
Or... Temporarily disable Safari's WebSocket restrictions — you can try going to Safari → Settings → Advanced → enable the Develop menu, then check Develop → Disable Local File Restrictions or similar options.