Comment 3 for bug 278757

I'm not seeing 241887, but two instances of Remix don't run concurrently (desktop icons are rendered poorly and performance is poor).

Reproduce:
Log-in as user1
Switch to user2 (user switch, not log-out/log-in)

I don't see a way to disable the user switching option in the Remix "Quit" dialog. I do have switching disabled from the locked-screen sign-in, but that setting isn't honored by Remix.