This is similar to bug 1518468 but doesn't affect the reftest part of Marionette. Not sure if it can be fixed at the same time, but if not we should have this filed for tracking the Fission work.

https://searchfox.org/mozilla-central/rev/b712398b7fae54ef377a558d6f16dede7a7f8530/testing/marionette/listener.js#378

 observe(subject, topic) {
    const win = curContainer.frame;
    const winID = subject.QueryInterface(Ci.nsISupportsPRUint64).data;
    const curWinID = win.windowUtils.outerWindowID;
    [..]

(In reply to Henrik Skupin (:whimboo) [⌚️UTC+2] from comment #0)

This is similar to bug 1518468 but doesn't affect the reftest part of Marionette. Not sure if it can be fixed at the same time, but if not we should have this filed for tracking the Fission work.

In that case, I'll track this bug for Fission's Nightly miletone (M6).

The priority flag is not set for this bug.
:whimboo, could you have a look please?

For more information, please visit auto_nag documentation.

Because this bug's Severity has not been changed from the default since it was filed, and it's Priority is P3 (Backlog,) indicating it has been triaged, the bug's Severity is being updated to S3 (normal.)

Note that right now we don't make use of the browsing context id for identifying the various frames in content but the outer window id. With my upcoming changes on bug 1519335 we will switch to browsing contexts. So I assume this might help to get this bug fixed?

Actually the code referred to here is all in navigation and will be removed with my work over on bug 1612831. I hope to have this done soon.

Since this depends on bug 1612831 which is tracked for M6b, I'm moving this also to the same milestone.

This code is no longer present on mozilla-central. Marking as fixed by bug 1612831.