I would be really nice if you were able to ctrl +click the items that show in the Plumber loot window to display in the dressing room in the same way you can if you click the item or the link in the chat window.

Hi! It's now a base feature in the Plumber Loot Window. However, the loot notification will not pause when you're viewing the item, so when you view an item and move the cursor away from our UI, it will fade out in a second.