New Features

stats: Expose the effective client authority (sent on the wire as the HTTP/2 :authority header) in client stats.OutHeader events. (#9296)
- Special Thanks: @aryansk
metadata: Add ValueFromOutgoingContext, which reads a single metadata value from outgoing context without copying the entire outgoing metadata into a new map. (#9282)
- Special Thanks: @yuyangguo42

Bug Fixes

transport: Refine control buffer throttling to only count peer-induced control frames, raise the default GRPC_GO_EXPERIMENTAL_CONTROL_BUFFER_THROTTLE_LIMIT from 100 to 10,000, and close client connections if reads remain throttled for 10s. (#9563)
server: Ensure Stop() forcefully terminates the server while GracefulStop() is waiting for active handlers to complete. (#9394)
- Special Thanks: @stanhu
server: Unconditionally increment the highest-seen stream ID on when handling HEADERS frames to comply with RFC 7540 §5.1.1. Previously, truncated HEADERS frames left the connection in an inconsistent state and allowed stream IDs to be reused by clients without resulting in a protocol error. (#9414)
server: Terminate streams immediately when a HEADERS frame includes the EndStream bit. Previously, this caused server handlers to hang when reading a message. (#9391)
server: Reject requests missing both :authority and Host headers with HTTP 400 and status Internal. (#9365)
xds: Fix a bug where route header matchers with non-lowercase names failed to match routes. (#9353)
- Special Thanks: @winklemad
client: Ensure retried RPCs use the correct :authority value specified by the LB policy instead of inheriting it from a previous attempt. (#9277)
- Special Thanks: @nvxbug
transport: Fail streams with io.ErrUnexpectedEOF instead of io.EOF upon receiving truncated message headers or bodies after partial data has already been received. (#9204)
- Special Thanks: @buger