How to select more than one route in Switching dropdown?

Hello,

i am using TS2015 SP1 and SwitchExec 2015. I created a list of routes that are now visible in the step-properties "Switching" in the dropdown-field "Route(s) to connect".

Here i can click on one item in the list to select it.

What can i do to select a second item from the dropdown-list?

It looks as i have to write the second item after the comma manually. Ist this correct? Or is there a trick to select again from the dropdown?

Thanks for help