[maxdeliso]

>Howell knows how to do this

well why doesn't he explain how we safely present a system API to arbitrary code?

the whole point of the browser is to provide a method for cross platform ui, abstracting the display of an application from the underlying OS. if you were to want to support more than one operating system you'd have to recompile your binaries against all the system APIs that you wanted to support, sysV, winnt, darwin, etc...

and if you were to present an abstraction which would transparently handle the system API difference then you're looking at a JVM, which has been painfully demonstrated to be extremely hard to prevent escalations for, time and time again.