Fix: Bootstrap 4 flexbox grid

[stroebjo]

The flexbox enabled grid in bootstap 4 requires the lowest .col- to be set. twbs/bootstrap#17603 (comment)

[DataTables]

I'm afraid I don't quite understand. If the viewport is less than md then I want the columns to be broken up into rows. Has that changed in v4? The docs don't seem to reflect such a change.

[stroebjo]

In the classic float grid it works in v4, but when you enable flexbox in Bootstrap the rows wont be 100% width. See the attached screens.
If you use the flexbox grid the grid cells dont fallback to 100% width, on lower breakpoints, you need to explictly define die lower breakpoints (col-xs-12).

Classic float grid in v4, centered cells on xs.

Flexbox grid, without col-xs-12, rows stick to left.

Flexbox grid, added col-xs-12, works as expected.

[DataTables]

Ah I see - thanks for the clarification. I wonder if we should wait for the BS issue you linked to to be resolved before making changes here.

[DataTables]

Sorry its taken me so long to get around to this! I agreed, based on mdo's comment's in that bug that your fix is correct. Thanks!