Add comment doc to USE_FROZEN_DICTS

synapse/events/__init__.py

@@ -53,16 +53,17 @@
 if TYPE_CHECKING:
     from synapse.events.builder import EventBuilder
 
-# Whether we should use frozen_dict in FrozenEvent. Using frozen_dicts prevents
-# bugs where we accidentally share e.g. signature dicts. However, converting a
-# dict to frozen_dicts is expensive.
-#
-# NOTE: This is overridden by the configuration by the Synapse worker apps, but
-# for the sake of tests, it is set here while it cannot be configured on the
-# homeserver object itself.
 
-USE_FROZEN_DICTS = strtobool(os.environ.get("SYNAPSE_USE_FROZEN_DICTS", "0"))
+USE_FROZEN_DICTS = False
+"""
+Whether we should use frozen_dict in FrozenEvent. Using frozen_dicts prevents
+bugs where we accidentally share e.g. signature dicts. However, converting a
+dict to frozen_dicts is expensive.
 
+NOTE: This is overridden by the configuration by the Synapse worker apps, but
+for the sake of tests, it is set here because it cannot be configured on the
+homeserver object itself.
+"""
 
 T = TypeVar("T")