Comment 3 for bug 1043816

It might stay hidden if you add the plugin inside another container, and set that container to display: none (in that case, the plugin should never get a frame).

But there might be another way, which would actually solve a couple of other things I've been thinking about. It might be possible to embed this in to the hidden window instead, and only embed it when it's first needed. The other issues this would solve are:

- Plugin startup is currently on the critical path at startup, and the startup budget is already tight (and spawning plugin-container is synchronous IIRC)
- You could share a single plugin instance across windows, rather than having one instance per window.

I'm not even sure that would work yet, but I might try it out later (unless there's another reason to have one instance per window?)