Support for Legacy Unity Version

[keli95566]

Hi there! I am currently working on a special SDK stack where I would need to use Unity Editor 2019.4 and lower in order to access Unity"s legacy VR system.
This might seem strange, but Unity 2019.4 is the only Editor that supports OpenGL on windows with SteamVR and OpenVR.
Our application depends on OpenGL and it would be really nice to have all the projects about Unity robotics working in the older editor versions as well.
Could you please instruct me if this would be possible at all, and what I would need to modify? Thank you!