Its small, its simple, its desperately needed on many vendors. We need to be able to go back and forth without having to close and re open the vendor if we are purchasing multiple items of different types from a single vendor. the current process is overly click heavy and cumbersome. I've made the suggestion before but it fell on deaf ears. Now, is the perfect time for you to do this, you're "reworking" the game already. Please consider this minor request.