normalizedlist.flatmap no es una función vue draggable

TypeError: normalizedList.flatMap is not a function
    at computeNodes (https://merchant-console.test/js/vendor.js:124305:37)
    at computeComponentStructure (https://merchant-console.test/js/vendor.js:124344:15)
    at Proxy.render (https://merchant-console.test/js/vendor.js:124465:32)
    at renderComponentRoot (https://merchant-console.test/js/vendor.js:29923:44)
    at componentEffect (https://merchant-console.test/js/vendor.js:33348:53)
    at reactiveEffect (https://merchant-console.test/js/vendor.js:28121:24)
    at effect (https://merchant-console.test/js/vendor.js:28096:9)
    at setupRenderEffect (https://merchant-console.test/js/vendor.js:33331:82)
    at mountComponent (https://merchant-console.test/js/vendor.js:33290:9)
    at processComponent (https://merchant-console.test/js/vendor.js:33250:17)
Wrong Wolverine