Collapse the grouped lines instead (or in addition) of scrolling a lot

[DroidTeo]

I personally like the idea to collapse the grouped lines instead of scrolling and scrolling.. 
For example, in a case like shown below, I could just click on the grouping element and with 2 clicks reduce a lot the space that I need to scroll 

Note My idea is to stay on te same view. So adding the RowNumber is not exactly what I'm thinking about

More like using a kind of accordion. 
Here a very simple example of what I mean: 
https://getbootstrap.com/docs/5.0/components/accordion/ 

[Steve]

Add an additional Group by column using the _RowNumber column. This should give you what you want.

[DroidTeo]

@Steve yes and no.. 
I mean, you cannot click on the header of each group to collapse and expand.
adding the RowNumber, the lines are collapsed by default, that's good, but once you click on on one groupe you are redirect to another list.

My idea is to stay on te same view. 

More like using a kind of accordion. 
Here a very simple example of what I mean: 
https://getbootstrap.com/docs/5.0/components/accordion/