Migracja z wersji Vue 2 na Vue 3

src/vuex.d.ts

@@ -0,0 +1,14 @@
+import { ComponentCustomProperties } from 'vue'
+import { Store } from 'vuex'
+
+declare module '@vue/runtime-core' {
+  // declare your own store states
+  interface State {
+    count: number
+  }
+
+  // provide typings for `this.$store`
+  interface ComponentCustomProperties {
+    $store: Store<State>
+  }
+}