Add support for emulate_network: Offline #320
Description
It would be very useful to have the ability to simulate offline network conditions directly through the MCP emulate_network command, similar to how it's possible in DevTools.
Currently, the command doesn’t support an Offline state, which limits testing for PWA and offline-first web applications. Adding this option would make it easier to automate and validate offline behavior through MCP scripts or tools that rely on this API.