After doing some digging we can conclude that at this stage collection-repeat can not be used when the height of an item is unknown before the list renders. For instance when your items consists of text elements that have varying lengths. One item might have 20 characters leading it to have one height, the other item might have 8 characters, giving it a smaller height. In this scenario, collection-repeat is not useable in its current form.
More information can be found here:
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