How to cancel a game which is in searching for players mode

[lexlogan8]

When I've launched a game and it's searching for players, I don't understand how to cancel it, except to close the window or tab (that is, close BGA.) Seems clumsy, is there nothing on the game screen that gets rid of it? Cancel may stop it but not close the search, and if I try to launch the game again it reports I've already got a table open.