I've added a needs-implementation label as part of the typical "new MSC" flow. I have yet to look at the linked implementation to see if it accurately reflects the MSC.

It's been mentioned OOB that this has an implementation and so should be safe to remove the needs-implementation label, however I believe that we're not quite there yet. It's great to see that this has active implementations in Element, though for a feature of this size, scale, and importance it's more valuable to have several clients adopt the MSC as an implicit show of support for the technical direction. Specifically, we'd want to see clients with implementation in front of users for enough time to reveal any usability issues.

For clarity, this does not need to be done in Element either. Element can serve as one of the implementations (if adopted), but generally would be a small percentage of the overall consideration.