In this video I describe how Vuetify's v-menu can return a variable to its previous state if the (undocumented) save function on v-menu is not called.
The variable passed to the v-menu "return-value" prop is captured when the v-menu is changed to visible (active). The state is reverted to that captured state if the (undocumented) "save()" function on v-menu is not called before the menu is closed/hidden.
The prop should also be called return-value.sync as it cannot return the value to the original state without the v-menu component being able to set the passed variable. It is useless without the ".sync".