A good point . open the Network tab" isn't a real answer for most people, and "trust me" isn't either.

Two things that don't depend on either: (1) the offline test is something anyone can do ,load the page, turn off your wifi, and the tools keep working, which they couldn't if they relied on a server; (2) the site ships a Content-Security-Policy that blocks outbound connections, so it's the browser enforcing it, not my word. The real fix for trust is open-sourcing it and getting a third-party audit, which is on my list.

Appreciate you pushing on this.