Full list of differences found in [this compare](https://github.com/open-telemetry/opentelemetry-proto/compare/v0.18.0...v0.19.0).
Changed
* Add `csharp_namespace` option to protos.
([399](https://github.com/open-telemetry/opentelemetry-proto/pull/399))
* Fix some out-of-date urls which link to [specification](https://github.com/open-telemetry/opentelemetry-specification). ([#402](https://github.com/open-telemetry/opentelemetry-proto/pull/402))
* :stop_sign: [BREAKING] Delete deprecated InstrumentationLibrary,
InstrumentationLibraryLogs, InstrumentationLibrarySpans and
InstrumentationLibraryMetrics messages. Delete deprecated
instrumentation_library_logs, instrumentation_library_spans and
instrumentation_library_metrics fields.
Added
* Introduce Scope Attributes. [395](https://github.com/open-telemetry/opentelemetry-proto/pull/395)
* Introduce partial success fields in `Export<signal>ServiceResponse`.
[414](https://github.com/open-telemetry/opentelemetry-proto/pull/414)