Does this point of view have or need a name? Something which conveys both the mental model and the possibility? At first thought it might be something like "sa

Does this point of view have or need a name? Something which conveys both the mental model and the possibility? At first thought it might be something like "sandbox javascript to the DOM". Relatedly, I don't know if there is a common name for the part of a tabbed browser which implements policy and defaults above the level of individual tabs. In some sense it is a kind of shell and sandboxer (?). Do we need a more shell-agnostic approach??