Vanilla JavaScript not working in Symfony4

I installed webpack encore on a Symfony 4 project but my vanilla javascript is not working. I can use jQuery.Here is part of the code structure:

webpack.config.js

var Encore = require('@symfony/webpack-encore');
// Manually configure the runtime environment if not already configured yet by the "encore" command.
// It's useful when you use tools that rely on webpack.config.js file.
if (!Encore.isRuntimeEnvironmentConfigured()) {
    Encore.configureRuntimeEnvironment(process.env.NODE_ENV || 'dev');
}
Encore
    // directory where compiled assets will be stored

    .setOutputPath('public/build/')

    // public path used by the web server to access the output path

    .setPublicPath('/build')

    // only needed for CDN's or sub-directory deploy

    //.setManifestKeyPrefix('build/')



    /*

     * ENTRY CONFIG

     *

     * Add 1 entry for each "page" of your app

     * (including one that's included on every page - e.g. "app")

     *

     * Each entry will result in one JavaScript file (e.g. app.js)

     * and one CSS file (e.g. app.css) if your JavaScript imports CSS.

     */

    .addEntry('app', './assets/js/app.js')

    .addEntry('login', './assets/js/login.js')

    .addEntry('non_financial_details', './assets/js/non_financial_details.js')

    //.addEntry('page2', './assets/js/page2.js')

    .copyFiles({

        from: './assets/img',

        to: 'img/[path][name].[ext]',

        pattern: /\.(png|jpg|jpeg|gif)$/

    })

    // When enabled, Webpack "splits" your files into smaller pieces for greater optimization.

    .splitEntryChunks()



    // will require an extra script tag for runtime.js

    // but, you probably want this, unless you're building a single-page app

    .enableSingleRuntimeChunk()



    /*

     * FEATURE CONFIG

     *

     * Enable & configure other features below. For a full

     * list of features, see:

     * https://symfony.com/doc/current/frontend.html#adding-more-features

     */

    .cleanupOutputBeforeBuild()

    .enableBuildNotifications()

    // allow legacy applications to use $/jQuery as a global variable

     .autoProvidejQuery()

    .enableSourceMaps(!Encore.isProduction())

    // enables hashed filenames (e.g. app.abc123.css)

    .enableVersioning(Encore.isProduction())



    // enables @babel/preset-env polyfills

    .configureBabelPresetEnv((config) => {

        config.useBuiltIns = 'usage';

        config.corejs = 3;

    })



    // enables Sass/SCSS support

    //.enableSassLoader()



    // uncomment if you use TypeScript

    //.enableTypeScriptLoader()



    // uncomment to get integrity="..." attributes on your script & link tags

    // requires WebpackEncoreBundle 1.4 or higher

    //.enableIntegrityHashes(Encore.isProduction())



    // uncomment if you're having problems with a jQuery plugin

    //.autoProvidejQuery()



    // uncomment if you use API Platform Admin (composer req api-admin)

    //.enableReactPreset()

    //.addEntry('admin', './assets/js/admin.js')

;

module.exports = Encore.getWebpackConfig();

app.js

require('../css/app.css');

require('jquery/dist/jquery.js');

//require('popper.js/dist/umd/popper.js');

require('bootstrap/dist/js/bootstrap.js');

require('bootstrap/dist/css/bootstrap.css');

non_financial_details.js

require('../css/permudb.css');

$(document).ready(function () {

$('form[name="non_financial_details"]').on("change",".target-actuals",function(e) {

var target_output_name=$(this).attr('name');
var result = target_output_name.split('_');
var indicator=result[0];
var tr= $(this).closest('tr');
var cum_semitot=0;
if (target_output_name.indexOf("qtr1") >= 0){
cum_semitot=parseInt($(this).val())+parseInt($("input[name='"+indicator+"_qtr2']").val());
$('td:nth-child(5)',tr).text(cum_semitot);
}else if (target_output_name.indexOf("qtr2") >= 0){
cum_semitot=parseInt($(this).val())+parseInt($("input[name='"+indicator+"_qtr1']").val());
$('td:nth-child(5)',tr).text(cum_semitot);
}
var cum_annualtot=parseInt($("input[name='"+indicator+"_qtr1']").val())+parseInt($("input[name='"+indicator+"_qtr2']").val())+parseInt($("input[name='"+indicator+"_qtr3").val())+parseInt($("input[name='"+indicator+"_qtr4']").val());
$('td:nth-child(8)',tr).text(cum_annualtot);

});



})

The three vanilla javascript functions: split(),indexof(), parseint() inside non_financial_details change event are not working.The presence of those functions make whole javascript including jquery fail. If I remove the whole code inside non_financial_details change event jQuery works. I am pretty sure that vanilla javascript functions are the culprit because even if I replace the code with simple code such as:

var str = "test_120";
var res = str.split("_");

It is still failing. Is there any explanation for this ?