import Vue from 'vue'
import Vuex from 'vuex'
import axios from 'axios'

Vue.use(Vuex)
Vue.use(axios)

Error message:

isURLSameOrigin.js?cf95:57 Uncaught (in promise) TypeError: Cannot
read property 'protocol' of undefined

at isURLSameOrigin (eval at <anonymous> (app.js:929), <anonymous>:57:21)
at dispatchXhrRequest (eval at <anonymous> (app.js:754), <anonymous>:108:50)
at Promise (<anonymous>)
at xhrAdapter (eval at <anonymous> (app.js:754), <anonymous>:12:10)
at dispatchRequest (eval at <anonymous> (app.js:866), <anonymous>:52:10)

Error screenshot:

But, using it in prototype mode is normal:

import Vue from 'vue'
import Vuex from 'vuex'
import axios from 'axios'

Vue.use(Vuex)
Vue.prototype.$ajax = axios