updated docs and changelog

Signed-off-by: metonymic-smokey <[email protected]>

CHANGELOG.md

@@ -25,7 +25,8 @@ We use *breaking :warning:* to mark changes that are not backward compatible (re
 - [#4552](https://github.com/thanos-io/thanos/pull/4552) Compact: Adds `thanos_compact_downsample_duration_seconds` histogram.
 - [#4594](https://github.com/thanos-io/thanos/pull/4594) reloader: Expose metrics in config reloader to give info on the last operation.
 - [#4623](https://github.com/thanos-io/thanos/pull/4623) query-frontend: made HTTP downstream tripper (client) configurable via parameters `--query-range.downstream-tripper-config` and `--query-range.downstream-tripper-config-file`. If your downstream URL is localhost or 127.0.0.1 then it is strongly recommended to bump `max_idle_conns_per_host` to at least 100 so that `query-frontend` could properly use HTTP keep-alive connections and thus reduce the latency of `query-frontend` by about 20%.
-- [#4636](https://github.com/thanos-io/thanos/pull/4636) Azure: Support authentication using user-assigned managed identity
+- [#4636](https://github.com/thanos-io/thanos/pull/4636) Azure: Support authentication using user-assigned managed identity  
+- [#4679](https://github.com/thanos-io/thanos/pull/4679) Added `enable-feature` flag to enable negative offsets and @ modifier, similar to Prometheus.  
 
 ### Fixed
 

docs/components/query.md

@@ -252,6 +252,9 @@ Query node exposing PromQL enabled Query API with data retrieved from multiple
 store nodes.
 
 Flags:
+      --enable-feature=...       Comma separated experimental feature names                                
+      				 to enable.The current list of features is                                 
+				 promql-negative-offset and promql-at-modifier.
       --grpc-address="0.0.0.0:10901"  
                                  Listen ip:port address for gRPC endpoints
                                  (StoreAPI). Make sure this address is routable