bsmedberg mentioned a while back that they were adding JS-ctypes access to E10S child processes. To help maintain confinement of Jetpack addons (specifically the code that runs outside of the main browser process), we'd like to turn this off. In particular, when the main process launches a new jetpack process, we'd like a flag that lets us disable js-ctypes in the child.
I'm not sure what Product/Component this should be attached to, but I'll start with jetpack and hope that someone who knows more than me can assign it appropriately.
For reference, bug 588563 is where ctypes were exposed to the jetpack process. Setting product/component to match.