FLuminPlatformFile::SetSandboxEnabled

Enables/disables application sandbox jail. When sandboxing is enabled all paths are prepended with the app root directory. When disabled paths are not prepended or checked for safety. For example, reading files from the directory /system/etc/security/cacerts requires reading from outside the app root directory, which cannot be done when sandboxing is enabled. Toggling the sandbox must be done manually by calling this function both before and after attempting to access any path outside of the app root directory. Only disable sandboxing when certain you know what you're doing.