How to duplicate group of cells without adding frames?

I have multiple layers, and want to duplicate cells that span 50 frames on one layer, but I don’t want to add frames, as i want to keep the other layers/frames the same. What is easiest way to do this?

  1. Do you mean cels (those circles in timeline) or cells (of grid)?
  2. For cels just select range of cels (click+drag), press Ctrl+C, then select starting cel (presumably empty) at another layer and press Ctrl+V