OffCanvas is always visible until you manually dismiss it, it seems the className “show” is added causing the OffCanvas to be visible on app launch.
When you dismiss the OffCanvas using the header X icon, the OffCanvas immediately disappears rather than slide closed.
After closing, then reopening the OffCanvas, the OffCanvas footer is no longer at the very bottom of the element, its now directly beneath the last element in the OffCanvas body.