In case when there's a few cards inside card-columns container they get distributed differently in Chrome, comparing to FF and Safari.

For example, with 2 cards, in Chrome they stay in the same column and are placed one under another. In FF and Safari they are distributed among 2 columns and displayed side by side.

Adding 3rd card leads to this: In chrome there are 2 cards in the 1st column and 1 in the 2nd. In other browsers there is 1 card in each of 3 columns.

Here is the reduced test case for 2 cards.
Here is the reduced test case for 3 cards.

I'm using BS4 alpha 3, running Mac Os 10.11.6, Chrome 53.0.2785.116 (64-bit), Firefox 49.0.1 and Safari 9.1.2 (11601.7.7).