In my case, I found a solution similar to JP Hellemons , in which I force the height of the placeholder (with importance) to adjust, as well as adjust the visibility with the background to see the changes for myself (you can also style your placeholder as you want).
This also works with display: inline-block;
.ui-sortable-placeholder { background:red !important; height: 2px !important;
user3780666 05 Oct '14 at 18:17 2014-10-05 18:17
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