v8.1.0
v8.1.5-snapshot
Seemingly randomly, I can no longer see anything in my session props in my Designer for two same-site but independent remote (across VPN) gateways, however for another site and VPN I can see the session props.
I can see this in the Designer diagnostics:
12:41:07.004 [Browser Thread: 53954] WARN Perspective.SessionProps - No designer store found on window!
Edit:
I can see the session params from a component binding 
It’s just come back for one of the servers, but not the other…