On my machine these tests WK1 plugin tests: compositing/plugins/composited-plugin.html compositing/plugins/no-backing-store.html compositing/plugins/small-to-large-composited-plugin.html always behave as if there is no plug-in, yet the tests pass on bots. Why the difference? Is there some plug-in installation or policy setting that run-webkit-tests is failing to control on user machines?
Probably! I do not know what it is, despite having looked into what machine specific things can still affect tests before.