MSC2175: Remove the creator field from m.room.create events (#2175)

Fixes #1193

Author: richvdh

proposals/2175-remove-creator-field.md

@@ -0,0 +1,17 @@
+# MSC2175: Remove the `creator` field from `m.room.create` events
+
+[`m.room.create`](https://matrix.org/docs/spec/client_server/r0.5.0#m-room-create)
+events have a mandatory `creator` property giving the ID of the user who
+created the room. This field is redundant as it is always identical to the
+`sender` of the create event.
+
+This MSC proposes that, in a future room version, this field should be removed
+and that the `sender` field be used instead.
+
+Note that `creator` is mentioned in the [auth
+rules](https://matrix.org/docs/spec/rooms/v1#authorization-rules). It can
+safely be removed.
+
+`creator` is also mentioned as a key to be preserved during [Event
+redaction](https://matrix.org/docs/spec/client_server/r0.5.0#redactions). It
+should be removed from that list.