You'd have to restrict localstorage and stuff like that too, else they could save data and then send it when they regain network access. If you have a use-case

You'd have to restrict localstorage and stuff like that too, else they could save data and then send it when they regain network access. If you have a use-case, or some ideas, there's Chrome bug page for "offline-only PWAs": https://bugs.chromium.org/p/chromium/issues/detail?id=995236 https://bugs.chromium.org/p/chromium/issues/detail?id=995236