Merge c94b54dab1 into 65b1db721d

We seem to have [updated this for m.room.name](https://github.com/matrix-org/matrix-spec/pull/1639) some years back but omitted it for topic.

changelogs/client_server/newsfragments/2068.clarification

@@ -0,0 +1 @@
+Clarify behaviour when the `topic` key of a `m.room.topic` event is absent, null, or empty.

changelogs/internal/newsfragments/2079.new

@@ -0,0 +1 @@
+Make disclosure of conflicts of interest mandatory for spec change proposals.

content/proposals.md

@@ -79,6 +79,19 @@ Please [see
 MSC1779](https://github.com/matrix-org/matrix-spec-proposals/blob/main/proposals/1779-open-governance.md)
 for full details of the project's Guiding Principles.
 
+For the purposes of transparency and to underpin the "greater benefit"
+principle, proposals MUST disclose possible conflicts of interest where
+they might reasonably exist. Authors MAY do this by filling out the
+following checklist and publishing it together with their proposal.
+
+```
+- [ ] I am being paid for working on this proposal by <ORGANIZATION>
+- [ ] I am an employee or member of <ORGANIZATION> which is involved in the Matrix ecosystem
+- [ ] I have another relationship that might appear to be a conflict of interest: <DETAILS>
+- [ ] I have some other type of financial interest in Matrix or this proposal: <DETAILS>
+- [ ] None of the above
+```
+
 ## Technical notes
 
 Proposals **must** develop Matrix as a layered protocol: with new
@@ -193,7 +206,8 @@ is as follows:
         filename that follows the format `1234-my-new-proposal.md` where
         `1234` is the MSC ID.
     -   Your PR description must include a link to the rendered Markdown
-        document and a summary of the proposal.
+        document and a disclosure of potential conflicts of interest where
+        they might reasonably apply.
     -   It is often very helpful to link any related MSCs or [matrix-spec
         issues](https://github.com/matrix-org/matrix-spec/issues) to give
         context for the proposal.

data/event-schemas/schema/m.room.topic.yaml

@@ -1,7 +1,14 @@
 ---
 allOf:
   - $ref: core-event-schema/state_event.yaml
-description: 'A topic is a short message detailing what is currently being discussed in the room.  It can also be used as a way to display extra information about the room, which may not be suitable for the room name. The room topic can also be set when creating a room using `/createRoom` with the `topic` key.'
+description: |- 
+    A topic is a short message detailing what is currently being discussed in the room.
+    It can also be used as a way to display extra information about the room, which may not
+    be suitable for the room name.
+    The room topic can also be set when creating a room using `/createRoom` with the `topic` key.'
+    
+    If the `topic` property is absent, null, or empty then the topic is unset. In other words,
+    an empty `topic` property effectively resets the room to having no topic.
 properties:
   content:
     properties: