Hi guys, this worked for me with the selection tags user input element.
example: https://hatlelukas.wixsite.com/mysite/repeater
exportfunction repeater1_itemReady($item, itemData, index)
{
//get tags from db for an item
let tags = itemData.tags;
//prepeate hashmap with tags to be diplayed
for (var i = 0; i < tags.length; i++) { options.push({"label": tags[i], "value": tags[i]}); }
//Set tags UI component $item("#selectionTags1").options = options;
}