Firestorm 6.4.21 + P373R VR Mod: This build includes P373R’s VR Mod 6.3.3 changes merged into Firestorm 6.4.21.64531 release branch. No change to the VR Mod code is needed. It is created using “GitHub Actions” (GHA) thanks to @humbletim. See latest release at https://github.com/humbletim/firestorm-gha/releases/
The user instructions are identical to Firestorm VR Mod 6.4.12 which is described at
https://blog.inf.ed.ac.uk/atate/2020/12/11/firestorm-vr-mod-6-4-12/
Update March 2022: Jumbled VR Initialisation Text:
I have noted that Ctrl+Tab to start the SteamVR/HMD device software sometimes shows jumbled letters for the VR driver initialisation message, and once that occurs using Tab to launch VR mode does not give a VR display in the HMD.
After some experimentation, I found that after starting Firestorm VR Mod, rather than going straight to Cltrl+Tab to set up for VR devices, I dismiss the message with tab, and THEN do a Ctrl+Tab the full message without missing letters immediately appears, and SteamVR/Oculus is launched and when the Tab is then used the VR mod works properly.
This may be a temporary situation and could be related to driver updates or SteamVR changes, but if you see the same thing, try the Tab and then Ctrl+Tab sequence to see if that also works for you.