Catalog items on categories page in Service Portal are not displaying. Instead you see a spinning wheel and nothings loads. See attached.
There is no option selected for the list view. It should be set to "Card" or "Grid". See attached.
Check user preferences table, filter for Name, where Name is "catalog-item-list-view". There should be a user preference where user column is blank and has a value of "Grid" or "Card". See attached. If there is not one with these values, adding one should fix the Issue. If there is one but the value is not one of the values mentioned previously, then it should be set to the correct value.