Enable room version 4

src/database/globals.rs

@@ -151,7 +151,7 @@ pub fn load(
         // Supported and stable room versions
         let stable_room_versions = vec![RoomVersionId::V6];
         // Experimental, partially supported room versions
-        let unstable_room_versions = vec![RoomVersionId::V5];
+        let unstable_room_versions = vec![RoomVersionId::V4, RoomVersionId::V5];
 
         let s = Self {
             globals,

src/database/rooms.rs

@@ -1845,7 +1845,6 @@ pub fn build_and_append_pdu(
             })
             .transpose()?;
 
-
         // If there was no create event yet, assume we are creating a room with the default
         // version right now
         let room_version_id = create_event_content