How to add short product tags when you already have long

I am trying to add a short product tag "heavy duty"

I already have lots of longer one like "heavy duty sample" but it wont accept a coma and take short one when I try and enter

where are the product tags stored? can I add to list manually if there is no work-around?

http://screencast.com/t/PuWkX64rr

Found the work around. Click outside the drop downbox to make it go away. Then add a comma and it is all good!!!