1 files changed, 7 insertions, 3 deletions
diff --git a/synapse/rest/client/read_marker.py b/synapse/rest/client/read_marker.py
index 8896f2df50..852838515c 100644
--- a/synapse/rest/client/read_marker.py
+++ b/synapse/rest/client/read_marker.py
@@ -40,9 +40,11 @@ class ReadMarkerRestServlet(RestServlet):
         self.read_marker_handler = hs.get_read_marker_handler()
         self.presence_handler = hs.get_presence_handler()
 
-        self._known_receipt_types = {ReceiptTypes.READ, ReceiptTypes.FULLY_READ}
-        if hs.config.experimental.msc2285_enabled:
-            self._known_receipt_types.add(ReceiptTypes.READ_PRIVATE)
+        self._known_receipt_types = {
+            ReceiptTypes.READ,
+            ReceiptTypes.FULLY_READ,
+            ReceiptTypes.READ_PRIVATE,
+        }
 
     async def on_POST(
         self, request: SynapseRequest, room_id: str
@@ -81,6 +83,8 @@ class ReadMarkerRestServlet(RestServlet):
                     receipt_type,
                     user_id=requester.user.to_string(),
                     event_id=event_id,
+                    # Setting the thread ID is not possible with the /read_markers endpoint.
+                    thread_id=None,
                 )
 
         return 200, {}