If a subscriber synchronously causes the same behavior to emit again,
rxjs delivers the nested value to every subscriber and then resumes
delivering the outer, older value to the remaining subscribers, which
leaves them permanently out of sync while .value holds the new value.
Queue nested emissions so every subscriber sees every value in order
and ends on the latest one, and warn once per behavior with a stack
trace so the re-entrant paths can be found.
This is the mode in which we sent membership events with the 'oldest membership' transport selection algorithm, which stopped being the default back in version 0.21.0. Users will no longer be able to select this mode in developer settings, and admins will no longer be able to select legacy mode through the config either. The app will still continue to support *receiving* membership events with the 'oldest membership' transport selection algorithm from others, however.
Support for events with an array of memberships from different devices was removed over a year ago in matrix-js-sdk ffd3c9575e9def576739baf6b1dc329b0db55c0c.
When someone starts or stops speaking, the layout will often be recomputed only to find out that there is ultimately no layout change. We can ignore these redundant updates to avoid re-rendering the InCallView and Grid components, which are relatively slow.
For that specific, common case, this reduces JS CPU usage by as much as 70% in my testing.
It turns out that the timers which repeatedly poll the RTP stats of each video track all run independently of each other and can add up to a small but constant sink of CPU. Meanwhile we can replace these timers with HTMLVideoElement 'resize' event listeners, which is way more efficient and reacts instantly to orientation changes.
Matthew Hodgson