Is there any way of changing the frame but keeping everything displayed in the 3D window just as it is? When keyframing, it would be good if you had the choice of either changing the frame first then modifying objects and keying (as is expected in Blender), or moving things around, then moving to the appropriate frame without having objects pulled back to their former keyed position. I’m prone to forgetting to set the frame before I make my modifications, and I always kick myself when I realise after wasting time getting things how i want them.
I guess you have to learn the right way
there is only really a way to do that for armatures, you would copy the pose to the buffer (only copies selected bones) then switch frames, then paste the pose.