HDOS has released their RuneLite plugin system into open beta. If you don’t know this client is a recreation of the 2009/2010 era client that contains the original HD update released in 2008.
The developers have also “remastered” several OSRS exclusive regions to be correctly textured and have that classic HD look.
Sadly if you’ve converted over to a Jagex account you cannot use this client yet. While it’s an approved third-party client it has not as of yet been added to the Jagex launcher.
To clarify: it is an HDOS client with a RuneLite-style plugin system? Or the other way around?
Yes, it’s a separate client that has RuneLite plugins as a separate system. They’re all working though, I was able to run through the recruitment drive series using quest helper in 2008 HD so it works as expected!
It is a HDOS client which utilizes the same plugin system as Runelite, ie. They will share plugins