Added

• Added an example of using metric views to customize instruments. (#3177)
• Add default User-Agent header to OTLP exporter requests (go.opentelemetry.io/otel/exporters/otlpmetric/otlpmetricgrpc and go.opentelemetry.io/otel/exporters/otlpmetric/otlpmetrichttp). (#3261)

Changed

• Flush pending measurements with the PeriodicReader in the go.opentelemetry.io/otel/sdk/metric when ForceFlush or Shutdown are called. (#3220)
• Update histogram default bounds to match the requirements of the latest specification. (#3222)

Fixed

• Use default view if instrument does not match any registered view of a reader. (#3224, #3237)
• Return the same instrument every time a user makes the exact same instrument creation call. (#3229, #3251)
• Return the existing instrument when a view transforms a creation call to match an existing instrument. (#3240, #3251)
• Log a warning when a conflicting instrument (e.g. description, unit, data-type) is created instead of returning an error. (#3251)
• The OpenCensus bridge no longer sends empty batches of metrics. (#3263)