Feature: Support for establishing HTTP/3 connections to upstream servers in the HTTP proxy module while allowing clients to use arbitrary HTTP versions. Configuration is done with the proxy_http_version directive and a set of proxy_quic_ and proxy_http3_ directives.
Feature: A mechanism for smoothly bringing the proxied server online after a failure using the slow_start option of the server directive in the upstream block.
Feature: mqtt_preread directive in the stream module, which allows extracting the username and client ID from the CONNECT packet of the MQTT protocol into the $mqtt_preread_username and $mqtt_preread_clientid variables.
Feature: Limiting the response rate of MP4 files transmission to the client proportionally to the bitrate using the mp4_limit_rate and mp4_limit_rate_after directives, which reduces the bandwidth load.
Feature: All functionality of nginx 1.25.3.
Bugfix: If a proxied server was the only one in a group, it could be incorrectly reported as unavailable in the metrics API even after recovery.