Phantom Websocket Pub Notification (cross-pod notification bug)

I am currently looking into notifications from the inbox using WebSockets over at uvdsl/solid-inbox-watcher.
(It seems that https://github.com/solid/node-solid-server/issues/933 could be closed?)

However, we ran into an odd thing:
Alice (aka. uvdsl, left hand side) and Bob (aka. ik1533, right hand side) both have their own pod on the same NSS.
When watching Alice's inbox, Alice receives a update notification via wss, when Bob's inbox is updated.

The PUB message Alice receives only contains "correct" data, i.e. the endpoint she subscribed to. But that resource wasn't updated...

MessageEvent {
isTrusted: true, 
data: 'pub https://uvdsl.solid.aifb.kit.edu/inbox/', 
origin: 'wss://uvdsl.solid.aifb.kit.edu', lastEventId: '', 
source: null, …}
isTrusted: true
bubbles: false
cancelBubble: false
cancelable: false
composed: false
currentTarget: WebSocket {url: 'wss://uvdsl.solid.aifb.kit.edu/inbox/', 
readyState: 1, bufferedAmount: 0, onerror: null, onopen: ƒ, …}
data: "pub https://uvdsl.solid.aifb.kit.edu/inbox/"
defaultPrevented: false
eventPhase: 0
lastEventId: ""
origin: "wss://uvdsl.solid.aifb.kit.edu"
path: []
ports: []
returnValue: true
source: null
srcElement: WebSocket {url: 'wss://uvdsl.solid.aifb.kit.edu/inbox/', readyState: 1, bufferedAmount: 0, onerror: null, onopen: ƒ, …}
target: WebSocket {url: 'wss://uvdsl.solid.aifb.kit.edu/inbox/', readyState: 1, bufferedAmount: 0, onerror: null, onopen: ƒ, …}
timeStamp: 38368.69999999972
type: "message"
userActivation: null
[[Prototype]]: MessageEvent

Other examples can be found at the corresponding issue in my app's repo: https://github.com/uvdsl/solid-inbox-watcher/issues/6

We tested it on solidweb.org and on another NSS 5.6.16
Do you have any idea as to why this happens?
Cheers

Start by reproducing the cross-pod notification in uvdsl/solid-inbox-watcher, especially the scenario described in its issue 6, using the reported solidweb.org or NSS 5.6.16 environments. Compare the subscription endpoint with the pod that was updated; done means an inbox watcher receives a notification only when its subscribed resource changes.