Possible Bug - 1.9 Spinner Fires on F5 Refresh

Possible Bug - 1.9 Spinner Fires on F5 Refresh

I have noticed that my spinner fires if it has focus when the user presses F5/Refresh. This happens even when the user has not made any changes to the spinner value in any way and the cursor is just sat in the field.

I have code in the spin stop that updates a shopping cart with an AJAX call, which is firing when the user refreshes the page. It shouldn't, and I was wondering whether I'll have to make a workaround, or whether it is a proble, with the spinner itself.

Is it a bug, or is it supposed to behave this way?

Cheers guys.