anchor.diff:  %%
   %% `opentelemetry_exporter' application enevironment options are:
   %%
  -%% * `otlp_endpoint': The URL to send traces and metrics to, for traces the
  -%%   path `v1/traces' is appended to the path in the URL.
  -%% * `otlp_traces_endpoint': URL to send only traces to. This takes precedence
  -%%   for exporting traces and the path of the URL is kept as is, no suffix is
  -%%   appended.
  -%% * `otlp_headers': Additional headers to add to export requests.
  -%% * `otlp_traces_headers': Additional headers to add to only trace export requests.
  +%% <ul>
  +%%   <li>
  +%%     `otlp_endpoint': The URL to send traces and metrics to, for traces the
  +%%     path `v1/traces' is appended to the path in the URL.
  +%%   </li>
  +%%   <li>`otlp_traces_endpoint': URL to send only traces to. This takes precedence
  +%%     for exporting traces and the path of the URL is kept as is, no suffix is
  +%%     appended.
  +%%   </li>
  +%%   <li>`otlp_headers': Additional headers to add to export requests.</li>
  +%%   <li>
  +%%     `otlp_traces_headers': Additional headers to add to only trace export %% requests.
  +%%   </li>
  +%% </ul>
   %%
   %% There also corresponding OS environment variables can also set those
   %% configuration values:
   %%
  -%% * `OTEL_EXPORTER_OTLP_ENDPOINT'
  -%% * `OTEL_EXPORTER_OTLP_TRACES_ENDPOINT'
  -%% * `OTEL_EXPORTER_OTLP_HEADERS'
  -%% * `OTEL_EXPORTER_OTLP_TRACES_HEADERS'
  +%% <ul>
  +%%   <li>`OTEL_EXPORTER_OTLP_ENDPOINT'</li>
  +%%   <li>`OTEL_EXPORTER_OTLP_TRACES_ENDPOINT'</li>
  +%%   <li>`OTEL_EXPORTER_OTLP_HEADERS'</li>
  +%%   <li>`OTEL_EXPORTER_OTLP_TRACES_HEADERS'</li>
  +%% </ul>
   %%
   %% @end
   %%%-------------------------------------------------------------------------
  
positive.code:                 grpc_metadata :: map() | undefined,
                  endpoints :: [uri_string:uri_map()]}).
  
  init(Opts0) ->
      Opts1 = merge_with_environment(Opts0),
      Endpoints = endpoints(maps:get(endpoints, Opts1, ?DEFAULT_ENDPOINTS)),
  
negative.code:             error
      end.
  
  %% @doc Shutdown the exporter.
  shutdown(#state{channel_pid=undefined}) ->
      ok;
  shutdown(#state{channel_pid=Pid}) ->
  