When you select multiple K2 categories, you'll notice that the options following the categories selector are "enabled". This allows you to enforce a different layout as the categories retrieved may differ in how they present items. However, if you're seeing items presented with their entire text, this means that the category(ies) these items belong to does(do) not filter just the introtext on listings. Or you're using a word limit and your content is basically just "introtext".

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