- Remove most usages of `update_membership` in favor
  of directly calling the `mark_as_*` functions
- Store the leave membership event as the value in the
  `userroomid_leftstate` table
- Use the `userroomid_leftstate` table to synchronize the
  timeline and state for left rooms if possible

@@ -0,0 +76,4 @@
+		a token which identifies the state of the room at a point in time.
+	2.  `load_timeline` is called to fetch timeline events that happened since `since`.
+	3.
+	*/

@@ -1199,0 +1202,4 @@
+# The default of 10 is reasonable for most use cases.
+#
+#incremental_sync_max_timeline_size = 10
+

@@ -480,0 +480,4 @@
+	// TODO: this call does not appear to do anything because `update_membership`
+	// doesn't call `mark_as_knock`. investigate further, ideally with the aim of
+	// removing this call entirely -- Ginger thinks `update_membership` should only
+	// be called from `force_state` and `append_pdu`.

@@ -0,0 +184,4 @@
+		.into();
+
+	let is_encrypted_room = services
+		.rooms

@@ -0,0 +201,4 @@
+		timeline_start_shortstatehash,
+		is_encrypted_room,
+	)
+	.await;

@@ -0,0 +262,4 @@
+		origin_server_ts: utils::millis_since_unix_epoch()
+			.try_into()
+			.expect("Timestamp is valid js_int value"),
+		kind: TimelineEventType::RoomMember,

@@ -445,1 +440,3 @@
-		.and_then(|val: Raw<Vec<AnyStrippedStateEvent>>| val.deserialize_as().map_err(Into::into))
+		// old databases may have garbage data as values in the `userroomid_leftstate` table from before
+		// the leave event was stored there. they still need to be included, so we return Ok(None) for deserialization failures.
+		.unwrap_or(None)

@@ -0,0 +451,4 @@
+	}
+
+	lazily_loaded_members
+}