You are correct, here it is the windowed borderless that works correctly, while unchecking it makes it unstable. But I suspect this is a bit dependent on your setup, so if you get random acceleration when windowed borderless I think it's just the same bug as I get when it's windowed.
Here's a video of the issue, every time the camera spins here the same script is executed. So as you can see it does first almost two turns (accelerated), then one turn exactly (which is correct), then almost two again (accelerated), then one exactly (correct).