Having an inspector open to a state that has a Parameter Driver will sometimes cause unity to spawn broken Animator windows and occasionally these will turn into "Failed to load..."

Attached are a few images of the symptoms of this bug

in , is called with focus = true (implicitly), this causes to be called on the window which does nothing if the window's m_Parent is set, but in very rare occasions during domain reloads (usually due to entering play mode) m_Parent is null, this causes unity to try spawning a new actual window for the , which ends up with the existing in multiple places at once which makes a lot of the unity windowing system to break, these duplicates continue to pile up during repeated domain reloads and can only be cleared via either a unity restart or layout reload.

This is obviously caused by some form of internal unity bug but the VRChat SDK should also not be calling with focus = true or calling at all because will create a window if one does not exist causing the inspector window to spawn an animator window when it is interacted with, this is clearly not desired behaviour.

should be used instead to find an without creating or focusing a window.

It might be even better to use and to get the controller that contains the directly.