SU5 Lag only while the camera is turning laterally

[JalopyJetsam]

I can report I am having this issue with SU5 and TrackIR:

1.18.13.0 (SU5) Stuttering and framerate drop when camera panning (TrackIR, mouse, joy hats)

Do you have any add-ons in your Community folder? If yes, please remove and retest before posting. No, all have been removed. Are you using Developer Mode or made changes in it? No. Only to provide diagnostic overlay in the provided video (link below) Brief description of the issue: When using TrackIR, mouse, joystick hats, panning or tilting of the camera results in significant framerate drops and stutter in SU5, including audio stutter. The impact of the problem appears dependent on the s…