matrix-org
Switching from SSS back to SS proxy causes to-device messages to be lost, causing UTDs
If the user switches from SSS back to using the proxy, we continue syncing with the old since tokens from SSS. This causes the proxy not to deliver any to-device events, hence leading to UTDs.
@manuroe Is it a bug we want to address considering we are sunsetting the proxy?
Would you object very much to keeping this issue open until we are confident that it will stop biting users? (Presumably, by removing the switch from the UI.)
I agree that we shouldn't invest resources in fixing it. Nevertheless it's extremely helpful to be able to keep track of the many reasons that users might encounter UTDs, and closing the issue gives the impression that we can rule this out as a potential cause of future UTDs?
It is a known issue now. It exits on the bug tracker. We know the plan for it, which is "Won't Fix". We can link to it even it is closed. These are the most important part. "Closed as not planned" adds useful another information to it, literally "Won't Fix". If you link such issue into a GH tasklist, it will appear as a task done but with a grey icon. This is super useful from an high level view.
Else, if we keep it open, we will have to reopen it everytime to check uts status and, then, it is likely to stay open forever because we are not good at issues cleanup.
Given matrix.org has turned off its sliding-sync proxy, I guess this is now unlikely to affect anyone.