As a model builder I want to have the similar feature to the Freeze cells (columns and rows) in Excel especially I want to be able to freeze top level element of the list used in a published module so no matter how I scroll the table it stays on the top or bottom of it and be able to select how top level elements of the grid are located.
Here is my draft:

The similar look should be for the columns - left/right part of the tableto have one total element always visible (i.e. to be able to see All periods)