IRHydra2 is deprecated. Supporting various V8 related features in IRHydra was always a race against the clock. V8 5.9 has switched to a new execution pipeline (TurboFan+Ignition) and modernizing IRHydra to properly work with it would be too much of a time investment for me, given that I don't need to dig into JavaScript performance anymore.

Ultimately IRHydra was always just a stopgap solution I created out of wooden sticks and duct tape. I always hoped that one day DevTools will be able to display all this information and more. Unfortunately this has not yet happened.

If you benefited from IRHydra in the past and think you will need a similar tool for modern V8 then please contact V8 Team and let them know your needs and requirements. A tool like IRHydra must be deeply integrated with the VM it targets to provide the best experience. Which means it should preferrably be maintained by the people who work on that VM.

You can find backup version of IRHydra2 here

— Vyacheslav Egorov (me@mrale.ph)