Trace from device interfaces passes through bridges to circuit termination, but not the other way around

[yrro]

I noticed that a cable traces from a device (router in my example) will pass through mutually-bridged interfaces on connected devices until they reach a circuit. However, the reverse trace (from termination Z in my example) stop at the directly connected device, rather than continuing until they reach the router.

I'm not sure if this is known, and/or if it's a bug. If so I can open an issue.

Here's a trace from a router through an ONT/ONU through to a circuit termination:

trace link

... and here's the reverse trace, from termination Z of the circuit:

trace link

[yrro]

Looks like this is issue #9800.