Bootstrap 4.4.0 added the row-cols-* classes (awesome job btw, so nice to have).

I did notice that it does not add classes for autosizing columns based on breakpoints and that might be something to add.

Consider the following case:

• For small devices we set .row-cols-2
• For medium devices .row-cols-md-4
• But for some reason we might want large devices to auto-size the columns, thus arises the need for .row-cols-lg-auto (not currently existing)

This is currently solvable by setting .row-cols-2.row-cols-md-4 on the row and then setting .col-lg-auto on the individual cols.

I think that this addition would give even greater flexibility in using the new .row-cols without the need to add classes to the nested columns.

I can create a PR for it, if we decide that it is a worthwhile addition. I read through parts of the discussion with row-cols but didn't manage to find anything regarding this (sorry if I have missed any prior discussions about it).