Leo, So in your reply you have done everything I have done. You created a list by selecting the category All Animals and assign the list to a widget. Up to this point it all works correctly. The posts from the All Animals category are displayed in sidebar widget. The problem is I don’t want this lists of posts displayed in the All Fruits category. How do I make WP Show Posts list only show in a specific category?
I put the code into the Snippets plugin and Lightweight Grids Columns and WP Show Posts shortcodes now work in category descriptions. Is this code stable? I mean the post from stackexchange is nearly two years old. Will I have to check on this each time a new WordPress update is released? Here is the code I inserted: