Remove the experimental config flag.

synapse/config/experimental.py

@@ -26,8 +26,6 @@ class ExperimentalConfig(Config):
     def read_config(self, config: JsonDict, **kwargs: Any) -> None:
         experimental = config.get("experimental_features") or {}
 
-        # MSC3440 (thread relation)
-        self.msc3440_enabled: bool = experimental.get("msc3440_enabled", False)
         # MSC3666: including bundled relations in /search.
         self.msc3666_enabled: bool = experimental.get("msc3666_enabled", False)
 

synapse/events/utils.py

@@ -39,7 +39,6 @@
 
 if TYPE_CHECKING:
     from synapse.handlers.relations import BundledAggregations
-    from synapse.server import HomeServer
 
 
 # Split strings on "." but not "\." This uses a negative lookbehind assertion for '\'
@@ -396,9 +395,6 @@ class EventClientSerializer:
     clients.
     """
 
-    def __init__(self, hs: "HomeServer"):
-        self._msc3440_enabled = hs.config.experimental.msc3440_enabled
-
     def serialize_event(
         self,
         event: Union[JsonDict, EventBase],

synapse/rest/client/versions.py

@@ -100,7 +100,6 @@ def on_GET(self, request: Request) -> Tuple[int, JsonDict]:
                     # Adds support for jump to date endpoints (/timestamp_to_event) as per MSC3030
                     "org.matrix.msc3030": self.config.experimental.msc3030_enabled,
                     # Adds support for thread relations, per MSC3440.
-                    "org.matrix.msc3440": self.config.experimental.msc3440_enabled,
                     "org.matrix.msc3440.stable": True,  # TODO: remove when "v1.3" is added above
                 },
             },

synapse/server.py

@@ -758,7 +758,7 @@ def get_oidc_handler(self) -> "OidcHandler":
 
     @cache_in_self
     def get_event_client_serializer(self) -> EventClientSerializer:
-        return EventClientSerializer(self)
+        return EventClientSerializer()
 
     @cache_in_self
     def get_password_policy_handler(self) -> PasswordPolicyHandler:

synapse/storage/databases/main/relations.py

@@ -14,7 +14,6 @@
 
 import logging
 from typing import (
-    TYPE_CHECKING,
     Collection,
     Dict,
     FrozenSet,
@@ -32,20 +31,12 @@
 from synapse.api.constants import RelationTypes
 from synapse.events import EventBase
 from synapse.storage._base import SQLBaseStore
-from synapse.storage.database import (
-    DatabasePool,
-    LoggingDatabaseConnection,
-    LoggingTransaction,
-    make_in_list_sql_clause,
-)
+from synapse.storage.database import LoggingTransaction, make_in_list_sql_clause
 from synapse.storage.databases.main.stream import generate_pagination_where_clause
 from synapse.storage.engines import PostgresEngine
 from synapse.types import JsonDict, RoomStreamToken, StreamToken
 from synapse.util.caches.descriptors import cached, cachedList
 
-if TYPE_CHECKING:
-    from synapse.server import HomeServer
-
 logger = logging.getLogger(__name__)
 
 
@@ -63,16 +54,6 @@ class _RelatedEvent:
 
 
 class RelationsWorkerStore(SQLBaseStore):
-    def __init__(
-        self,
-        database: DatabasePool,
-        db_conn: LoggingDatabaseConnection,
-        hs: "HomeServer",
-    ):
-        super().__init__(database, db_conn, hs)
-
-        self._msc3440_enabled = hs.config.experimental.msc3440_enabled
-
     @cached(uncached_args=("event",), tree=True)
     async def get_relations_for_event(
         self,