> Integrating a browser engine with the core operating system increases security...how? In particular, how process isolation and Just-In-Time compilers work.

> Integrating a browser engine with the core operating system increases security...how? In particular, how process isolation and Just-In-Time compilers work. Since mobile phones are extremely resource constrained, there's a tradeoff between security and performance that is more difficult on mobile than on the desktop. That means the way things were sandboxed on mobile was different on the desktop. For example, the ability to allocate memory that is both writable and executable, one of the features used by Javascript JITs, opens up a huge attack surface area. Apple basically solved this problem by making JavaScriptCore the only blessed Javascript engine able to do this, and for a long time, only Mobile Safari itself could leverage the JIT. Granted, modern phones can relax this, but there's definitely benefits to controlling the entire stack. For example, some functions of the browser could leverage enclaves or enclave-like containers for privacy oriented calculations.