Created attachment 354762 [details] preference->general tab (1) When Enable timeouts on "Save changes on closing question", in Edit->Preference->General tab, is checked and Time to wait for answer is set 0, "Save changes on closing question" windows will wait 2^32 seconds. (2) When Enable timeouts on "Save changes on closing question" is *NOT* checked, I can change Time to wait for answer option. I don't think both of them are good behavior. I recommended that the minimum value of Time to wait for answer option should be 1, and it should be grayed out (not editable) when Enable timeouts on "Save changes on closing question" is not checked.
Created attachment 354763 [details] save changes on closing window
Thanks for the report. Fixed as you suggested. This will be released in GnuCash 3.3.