Behavior Changes

• balancer: grpc will switch to case-sensitive balancer names soon; log a warning if a capital letter is encountered in an LB policy name (#6647)
• server: allow applications to send arbitrary data in the grpc-status-details-bin trailer (#6662)
• client: validate grpc-status-details-bin trailer and pass through the trailer to the application directly (#6662)

New Features

• tap (experimental): Add Header metadata to tap handler (#6652)
  • Special Thanks: @pstibrany
• grpc: channel idleness enabled by default with an idle_timeout of 30m (#6585)

Documentation

• examples: add an example of flow control behavior (#6648)

Bug Fixes

• xds: fix hash policy header to skip "-bin" headers and read content-type header as expected (#6609)