SQL Assistant 15.00

Hi there,
When running queries in a Query Tab, I remember that in previous versions, the colour of the tab would change to indicate that a query was running, and it would change again to indicate when the query had completed.
This functionality isn't working for me in 15.00 - whilst the query itself is highlighted while being executed, the colour of the never changes... I wonder if there's a setting I have missed?
Thanks