Try pushes for OSX with e10s enabled and have been seeing occasional leak-the-world style leaks. Thanks to run-by-dir, we can say with certainty that they're coming from dom/workers/test/serviceworkers. https://treeherder.mozilla.org/logviewer.html#?job_id=17372415&repo=try https://treeherder.mozilla.org/logviewer.html#?job_id=17293728&repo=try

There was already a bug on file for a service workers leak on Win7, so I'll just dupe this over to that and expand its scope. It is almost certainly the same issue, just worse on Win7.