I played 30 levels and then Chrome unloaded the tab, and now I'm sad that I have to do 90 clicks and wait for 30 level start animations to get back to where I was. Can you just make a full level select grid?
Fortunately one already exists! Just select the menu in the top left and then the "leave" option. Sorry it wasn't obvious! :)
Also, you might find that the arrow keys are easier to use than dragging on desktop/laptop ;)