Q:

Deprecation warning in my laravel./vuejs app with unused momentjs

In my laravel 5. Vuejs 2, Vuex 3 app I got warning in my console:
 Arguments: 
[0] _isAMomentObject: true, _isUTC: false, _useUTC: false, _l: undefined, _i: function Vue (options) {
  if (!(this instanceof Vue)) {
    warn('Vue is a constructor and should be called with the `new` keyword');
  }
  this._init(options);
}, _f: undefined, _strict: undefined, _locale: [object Object]
Error
    at Function.createFromInputFallback (http://local-hostels2.com/js/app.js?dt=1559733588:58205:98)
    at configFromInput (http://local-hostels2.com/js/app.js?dt=1559733588:60508:19)
    at prepareConfig (http://local-hostels2.com/js/app.js?dt=1559733588:60479:13)
    at createFromConfig (http://local-hostels2.com/js/app.js?dt=1559733588:60446:44)
    at createLocalOrUTC (http://local-hostels2.com/js/app.js?dt=1559733588:60533:16)
    at createLocal (http://local-hostels2.com/js/app.js?dt=1559733588:60537:16)
    at hooks (http://local-hostels2.com/js/app.js?dt=1559733588:57897:29)
    at Function.Vue.use (http://local-hostels2.com/js/app.js?dt=1559733588:108861:14)
    at Module../resources/js/app.js (http://local-hostels2.com/js/app.js?dt=1559733588:117240:44)
    at __webpack_require__ (http://local-hostels2.com/js/app.js?dt=1559733588:20:30)

composer.json :
{
    "name": "laravel/laravel",
    "type": "project",
    "description": "The Laravel Framework.",
    "keywords": [
        "framework",
        "laravel"
    ],
    "license": "MIT",
    "require": {
        "php": "^7.1.3",
        "fideloper/proxy": "^4.0",
        "fzaninotto/faker": "^1.8",
        "intervention/image": "^2.4",
        "laracasts/utilities": "^3.0",
        "laravel/framework": "5.7.*",
        "laravel/tinker": "^1.0",
        "orangehill/iseed": "^2.6",
        "pusher/pusher-php-server": "^3.4",
        "tymon/jwt-auth": "^1.0.0",
        "wboyz/laravel-enum": "^0.2.1",
        "zizaco/entrust": "^1.9"
    },
    "require-dev": {
        "beyondcode/laravel-dump-server": "^1.0",
        "beyondcode/laravel-query-detector": "^1.0",
        "filp/whoops": "^2.0",
        "mockery/mockery": "^1.0",
        "nunomaduro/collision": "^2.0",
        "phpunit/phpunit": "^7.0",
        "xethron/migrations-generator": "^2.0"
    },
    "config": {
        "optimize-autoloader": true,
        "preferred-install": "dist",
        "sort-packages": true
    },
    "extra": {
        "laravel": {
            "dont-discover": []
        }
    },
    "autoload": {
        "psr-4": {
            "App\\": "app/"
        },
        "classmap": [
            "database/seeds",
            "database/factories"
        ]
    },
    "autoload-dev": {
        "psr-4": {
            "Tests\\": "tests/"
        }
    },
    "minimum-stability": "dev",
    "prefer-stable": true,
    "scripts": {
        "post-autoload-dump": [
            "Illuminate\\Foundation\\ComposerScripts::postAutoloadDump",
            "@php artisan package:discover --ansi"
        ],
        "post-root-package-install": [
            "@php -r \"file_exists('.env') || copy('.env.example', '.env');\""
        ],
        "post-create-project-cmd": [
            "@php artisan key:generate --ansi"
        ]
    }
}

My package.json :
{
    "private": true,
    "scripts": {
        "dev": "npm run development",
        "development": "cross-env NODE_ENV=development node_modules/webpack/bin/webpack.js --progress --hide-modules --config=node_modules/laravel-mix/setup/webpack.config.js",
        "watch": "npm run development -- --watch",
        "watch-poll": "npm run watch -- --watch-poll",
        "hot": "cross-env NODE_ENV=development node_modules/webpack-dev-server/bin/webpack-dev-server.js --inline --hot --config=node_modules/laravel-mix/setup/webpack.config.js",
        "prod": "npm run production",
        "production": "cross-env NODE_ENV=production node_modules/webpack/bin/webpack.js --no-progress --hide-modules --config=node_modules/laravel-mix/setup/webpack.config.js"
    },
    "devDependencies": {
        "axios": "^0.19.0",
        "bootstrap": "^4.3.1",
        "cross-env": "^5.1",
        "jquery": "^3.4.0",
        "laravel-mix": "^4.0.15",
        "lodash": "^4.17.5",
        "popper.js": "^1.15.0",
        "resolve-url-loader": "^2.3.2",
        "sass": "^1.19.0",
        "sass-loader": "^7.1.0",
        "vue": "^2.6.10",
        "vue-template-compiler": "^2.6.10"
    },
    "dependencies": {
        "font-awesome": "^4.7.0",
        "laravel-echo": "^1.5.3",
        "marked": "^0.6.2",
        "moment": "^2.24.0",
        "pusher-js": "^4.4.0",
        "vee-validate": "^2.2.5",
        "vee-validate-laravel": "^1.1.0",
        "vue-carousel": "^0.18.0",
        "vue-color": "^2.7.0",
        "vue-focus": "^2.1.0",
        "vue-form-wizard": "^0.8.4",
        "vue-js-modal": "^1.3.28",
        "vue-jstree": "^2.1.6",
        "vue-moment": "^4.0.0",
        "vue-nav-tabs": "^0.5.7",
        "vue-notification": "^1.3.16",
        "vue-router": "^3.0.6",
        "vue-select": "^2.6.4",
        "vue-wysiwyg": "^1.7.2",
        "vue2-filters": "^0.6.0",
        "vuejs-paginate": "^2.1.0",
        "vuex": "^3.1.0"
    }
}

Actually momentjs is not installed/used in my app, that can be checked in config files above.
It seems not critical now, but I would like to fix it anyway...
Can you please give a hint what could raise this warning and how to fix it?
Thanks!    

A:

Well, are you sure you don't use the vue-moment plugin in your code? We can read "vue-moment": "^4.0.0", in your packages.json file. I don't have access to your code but I imagine you're using it somewhere in your code. In your error, we can read arguments that contains _isAMomentObject: true... It should be somewhere a moment object.

