Getting the GLFW context of "Simulate" in Python

[bd-jmiller2]

The feature, motivation and pitch

Hi, as a follow up to #766 (and also somewhat related to #965):
I am running mujoco passive viewer via mujoco.launch_passive in python (which is a wrapper around mujoco simulate.cc). I would like to have access to the GLFW window/ mjrContext so that I can:

• run mjr_figure to add custom 2D plots to the viewer, which requires access to the mjrContext
• add custom imgui overlays to the mujoco viewer by rendering to the same GLFW context/window
• create/render mjui (e.g. mjui_render) which requires access to mjrContext.

Alternatives

Currently it seems like the workaround would either be to render everything else in a separately managed glfw window or copy and modify the launch_passive/simulate functionality so that we have access to this?

Additional context

No response