I feel this is working as Intended. Such intranet sites are themselves broken by virtue of ICANN's policies around delegating them in the first place. We also have in place the ICANN transition to warn users, particularly for cases like http://foo.dev

Unqualified hostnames should never be able to opt-in to HSTS. As a result of ICANN's policy decisions, unqualified hostnames are effectively 'squatters', and should be considered deprecated and, as captured in SSAC policy, a security risk.

In order to avoid confusion, when writing HSTS names I write, say, (*.)dev and (*.)app in order to try and convey exactly what is covered.

I think I agree with sleevi here that these are now global names and we shouldn't pretend otherwise.

(Removing the bug from the enterprise triage queue as the corresponding owners seem to be involved already.)

If the Enterprise team isn't screaming about us blowing up Intranets, then SGTM.