woocomerce change product display

Hi!

Today I have upgraded to Woocommerce 3.8 from version 2.3.11. Everything went fine. Only, after the upgrade, before activating Woocommerce again I was returned a list of warnings and fatal errors in the frontend, one of which pointed to the child theme of i-craft. Everything fixed as soon I actived the new version of Woocommerce from backend.
So I have no other problems, but the products in the category page are displayed differently than before: they are 2 each line, instead of 4.
I’m not sure what could cause this change? May you give me some clue on this?
I’m running i-craft theme version 1.1.1 with child theme. In my child theme, I have

// Store column count for displaying the grid
if ( empty( $woocommerce_loop['columns'] ) )
	$woocommerce_loop['columns'] = apply_filters( 'loop_shop_columns', 4 );

So I suppose products should organized in 4 columns?

Many thanks in advance