diff --git a/resources/assets/src/js/__tests__/admin.test.js b/resources/assets/src/js/__tests__/admin.test.js
index a425cbe1..5f9b1358 100644
--- a/resources/assets/src/js/__tests__/admin.test.js
+++ b/resources/assets/src/js/__tests__/admin.test.js
@@ -548,16 +548,30 @@ describe('tests for "update" module', () => {
           file_size: 5000
         });
       })
-      .mockImplementationOnce(() => Promise.resolve());
+      .mockImplementationOnce(() => Promise.resolve())
+      .mockImplementationOnce(() => Promise.resolve({ msg: 'ok' }))
+      .mockImplementationOnce(() => Promise.reject())
+      .mockImplementationOnce(({ beforeSend }) => {
+        beforeSend && beforeSend();
+        return Promise.resolve({
+          file_size: 5000
+        });
+      })
+      .mockImplementationOnce(() => Promise.resolve())
+      .mockImplementationOnce(() => Promise.resolve({ msg: 'ok' }));
     const url = jest.fn(path => path);
     const toastr = {
       success: jest.fn(),
       warning: jest.fn()
     };
     const modal = jest.fn();
+    const swal = jest.fn()
+      .mockReturnValueOnce(Promise.resolve())
+      .mockReturnValueOnce(Promise.reject());
     window.fetch = fetch;
     window.url = url;
     window.toastr = toastr;
+    window.swal = swal;
     window.showAjaxError = jest.fn();
     $.fn.modal = modal;
 
@@ -565,6 +579,8 @@ describe('tests for "update" module', () => {
       <div id="file-size"></div>
       <div id="modal-start-download"></div>
       <button id="update-button"></button>
+      <div class="modal-title"></div>
+      <div class="modal-body"></div>
     `;
 
     const downloadUpdates = require(modulePath).downloadUpdates;
@@ -586,6 +602,38 @@ describe('tests for "update" module', () => {
       type: 'POST',
       dataType: 'json'
     });
+    expect($('.modal-title').html().includes('admin.extracting')).toBe(true);
+    expect($('.modal-body').html().includes('admin.downloadCompleted')).toBe(true);
+    expect(swal).toBeCalledWith({ type: 'success', html: 'ok' });
+    expect(url).toBeCalledWith('/');
+
+    await downloadUpdates();
+    expect(window.showAjaxError).toBeCalled();
+
+    await downloadUpdates();
+    expect(url).toBeCalledWith('/');
+  });
+
+  it('download progress polling', async () => {
+    const fetch = jest.fn().mockReturnValueOnce(Promise.resolve({ size: 50 }));
+    const url = jest.fn(path => path);
+    window.fetch = fetch;
+    window.url = url;
+
+    document.body.innerHTML = `
+      <div id="imported-progress"></div>
+      <div class="progress-bar"></div>
+    `;
+
+    const { progressPolling } = require(modulePath);
+    await progressPolling(100)();
+    expect(fetch).toBeCalledWith({
+      url: 'admin/update/download?action=get-file-size',
+      type: 'GET'
+    });
+    expect($('#imported-progress').html()).toBe('50.00');
+    expect($('.progress-bar').css('width')).toBe('50%');
+    expect($('.progress-bar').attr('aria-valuenow')).toBe('50.00');
   });
 
   it('check for updates', async () => {
diff --git a/resources/assets/src/js/__tests__/skinlib.test.js b/resources/assets/src/js/__tests__/skinlib.test.js
index 9d48cc19..3c29e767 100644
--- a/resources/assets/src/js/__tests__/skinlib.test.js
+++ b/resources/assets/src/js/__tests__/skinlib.test.js
@@ -1,6 +1,5 @@
 /* eslint no-unused-vars: "off" */
 
-jest.dontMock('jquery');
 const $ = require('jquery');
 window.$ = window.jQuery = $;
 
@@ -9,6 +8,30 @@ window.getQueryString = jest.fn((key, defaultValue) => defaultValue);
 describe('tests for "index" module', () => {
   const modulePath = '../skinlib/index';
 
+  it('initialize skin library', () => {
+    const fetch = jest.fn().mockReturnValue(Promise.resolve({ items: [] }));
+    const url = jest.fn(path => path);
+    const trans = jest.fn(key => key);
+    const showAjaxError = jest.fn();
+    window.fetch = fetch;
+    window.url = url;
+    window.trans = trans;
+    window.showAjaxError = showAjaxError;
+    $.fn.jqPaginator = jest.fn();
+    const { initSkinlib } = require(modulePath);
+
+    initSkinlib();
+    expect(fetch).not.toBeCalled();
+
+    document.body.innerHTML = `
+      <div id="skinlib-container"></div>
+      <div id="skinlib-paginator"></div>
+      <div class="sort"></div>
+    `;
+    initSkinlib();
+    expect(fetch).toBeCalled();
+  });
+
   it('render skin library', () => {
     const trans = jest.fn(key => key);
     const url = jest.fn(path => path);
@@ -216,12 +239,16 @@ describe('tests for "index" module', () => {
   it('change page', () => {
     document.body.innerHTML = `
       <div class="overlay" style="display: none"></div>
+      <select class="pagination">
+        <option value="2"></option>
+      </select>
     `;
     const { onPageChange } = require(modulePath);
     onPageChange(1, 'init');
     expect($.skinlib.page).toBe(1);
 
-    onPageChange(2);
+    //onPageChange(2);
+    $('select').trigger('change');
     expect($('div').css('display')).not.toBe('none');
     expect($.skinlib.page).toBe(2);
   });
@@ -238,11 +265,65 @@ describe('tests for "index" module', () => {
     updateFilter.call($('div'), new Event('click'));
     expect($.skinlib.uploader).toBe(4);
   });
+
+  it('change sort type', () => {
+    const fetch = jest.fn().mockReturnValue(Promise.resolve());
+    window.fetch = fetch;
+    document.body.innerHTML = `
+      <a class="sort" data-sort="likes"></a>
+    `;
+
+    require(modulePath);
+    $('a').click();
+    expect(fetch).toBeCalled();
+    expect($.skinlib.sort).toBe('likes');
+  });
+
+  it('search texture', async () => {
+    const fetch = jest.fn().mockReturnValue(Promise.resolve());
+    window.fetch = fetch;
+    document.body.innerHTML = `
+      <form id="search-form">
+        <input id="navbar-search-input" name="q" value="keyword">
+      </form>
+    `;
+
+    $('#search-form').trigger('submit');
+    expect(fetch).toBeCalled();
+    expect($.skinlib.keyword).toBe('keyword');
+  });
 });
 
 describe('tests for "operations" module', () => {
   const modulePath = '../skinlib/operations';
 
+  it('toggle liked', async () => {
+    const fetch = jest.fn().mockReturnValue(Promise.resolve());
+    const swal = jest.fn().mockReturnValue(Promise.resolve());
+    const url = jest.fn(path => path);
+    window.fetch = fetch;
+    window.swal = swal;
+    window.url = url;
+    document.body.innerHTML = `
+      <a tid="5" class="anonymous"></a>
+    `;
+    const { toggleLiked } = require(modulePath);
+
+    await toggleLiked.call($('a'));
+    expect(fetch).not.toBeCalled();
+
+    $('a').removeClass('anonymous');
+    const originGetJson = $.getJSON;
+    $.getJSON = jest.fn();
+    await toggleLiked.call($('a'));
+    expect($.getJSON).toBeCalled();
+    $.getJSON = originGetJson;
+
+    $('a').addClass('liked');
+    await toggleLiked.call($('a'));
+    expect(fetch).toBeCalled();
+  });
+
   it('add to closet', async () => {
     const url = jest.fn(path => path);
     window.url = url;
diff --git a/resources/assets/src/js/admin/update.js b/resources/assets/src/js/admin/update.js
index 844fce6d..6c7193b3 100644
--- a/resources/assets/src/js/admin/update.js
+++ b/resources/assets/src/js/admin/update.js
@@ -1,24 +1,22 @@
 'use strict';
 
-function downloadUpdates() {
-    var fileSize = 0;
-    var progress = 0;
+async function downloadUpdates() {
+    console.log('Prepare trno download');
 
-    console.log('Prepare to download');
+    try {
+        const preparation = await fetch({
+            url: url('admin/update/download?action=prepare-download'),
+            type: 'GET',
+            dataType: 'json',
+            beforeSend: function() {
+                $('#update-button').html(
+                    '<i class="fa fa-spinner fa-spin"></i> ' + trans('admin.preparing')
+                ).prop('disabled', 'disabled');
+            }
+        });
+        console.log(preparation);
 
-    fetch({
-        url: url('admin/update/download?action=prepare-download'),
-        type: 'GET',
-        dataType: 'json',
-        beforeSend: function() {
-            $('#update-button').html(
-                '<i class="fa fa-spinner fa-spin"></i> ' + trans('admin.preparing')
-            ).prop('disabled', 'disabled');
-        }
-    }).then(json => {
-        console.log(json);
-
-        fileSize = json.file_size;
+        const { file_size: fileSize } = preparation;
 
         $('#file-size').html(fileSize);
 
@@ -29,63 +27,65 @@ function downloadUpdates() {
 
         console.log('Start downloading');
 
-        fetch({
+        // Downloading progress polling
+        const interval_id = setInterval(progressPolling(fileSize), 300);
+
+        const download = await fetch({
             url: url('admin/update/download?action=start-download'),
             type: 'POST',
             dataType: 'json'
-        }).then(json => {
-            // Set progress to 100 when got the response
-            progress = 100;
+        });
 
-            console.log('Downloading finished');
-            console.log(json);
-        }).catch(showAjaxError);
+        clearInterval(interval_id);
 
-        // Downloading progress polling
-        let interval_id = setInterval(() => {
+        console.log('Downloading finished');
+        console.log(download);
+
+        $('.modal-title').html('<i class="fa fa-spinner fa-spin"></i> ' + trans('admin.extracting'));
+        $('.modal-body').append(`<p>${trans('admin.downloadCompleted')}</p>`);
+
+        console.log('Start extracting');
+
+        const extract = await fetch({
+            url: url('admin/update/download?action=extract'),
+            type: 'POST',
+            dataType: 'json'
+        });
+        
+        console.log('Package extracted and files are covered');
+        $('#modal-start-download').modal('toggle');
+
+        swal({
+            type: 'success',
+            html: extract.msg
+        }).then(function () {
+            window.location = url('/');
+        }, function () {
+            window.location = url('/');
+        });
+    } catch (error) {
+        showAjaxError(error);
+    }
+}
+
+function progressPolling(fileSize) {
+    return async () => {
+        try {
+            const { size } = await fetch({
+                url: url('admin/update/download?action=get-file-size'),
+                type: 'GET'
+            });
+            
+            const progress = (size / fileSize * 100).toFixed(2);
+    
             $('#imported-progress').html(progress);
-            $('.progress-bar').css('width', progress+'%').attr('aria-valuenow', progress);
-
-            if (progress == 100) {
-                clearInterval(interval_id);
-
-                $('.modal-title').html('<i class="fa fa-spinner fa-spin"></i> ' + trans('admin.extracting'));
-                $('.modal-body').append(`<p>${ trans('admin.downloadCompleted') }</p>`);
-
-                console.log('Start extracting');
-
-                fetch({
-                    url: url('admin/update/download?action=extract'),
-                    type: 'POST',
-                    dataType: 'json'
-                }).then(json => {
-                    console.log('Package extracted and files are covered');
-                    $('#modal-start-download').modal('toggle');
-
-                    swal({
-                        type: 'success',
-                        html: json.msg
-                    }).then(function() {
-                        window.location = url('/');
-                    }, function() {
-                        window.location = url('/');
-                    });
-                }).catch(showAjaxError);
-
-            } else {
-                fetch({
-                    url: url('admin/update/download?action=get-file-size'),
-                    type: 'GET'
-                }).then(json => {
-                    progress = (json.size / fileSize * 100).toFixed(2);
-
-                    console.log('Progress: ' + progress);
-                }).catch(showAjaxError);
-            }
-
-        }, 300);
-    }).catch(showAjaxError);
-
+            $('.progress-bar')
+                .css('width', progress + '%')
+                .attr('aria-valuenow', progress);
+        } catch (error) {
+            // No need to show error if failed to get size
+        }
+    };
 }
 
 async function checkForUpdates() {
@@ -104,6 +104,7 @@ async function checkForUpdates() {
 if (typeof require !== 'undefined' && typeof module !== 'undefined') {
     module.exports = {
         checkForUpdates,
+        progressPolling,
         downloadUpdates,
     };
 }
diff --git a/resources/assets/src/js/skinlib/index.js b/resources/assets/src/js/skinlib/index.js
index 341cc52d..10db1633 100644
--- a/resources/assets/src/js/skinlib/index.js
+++ b/resources/assets/src/js/skinlib/index.js
@@ -8,7 +8,31 @@ $.skinlib = {
     keyword:  decodeURI(getQueryString('keyword', ''))
 };
 
-$(document).ready(() => {
+$(document).ready(initSkinlib);
+
+$('body').on('change', 'select.pagination', function () {
+    onPageChange(parseInt($(this).val()));
+});
+
+$('.filter').click(updateFilter);
+
+$('body').on('click', '.sort', function (e) {
+    e.preventDefault();
+    $.skinlib.sort = $(this).data('sort');
+
+    console.log('Sort by ' + $.skinlib.sort);
+    reloadSkinlib();
+});
+
+$('body').on('submit', '#search-form', function (e) {
+    e.preventDefault();
+    $.skinlib.keyword = $('#navbar-search-input').val();
+
+    console.log('Search keyword: ' + $.skinlib.keyword);
+    reloadSkinlib();
+});
+
+function initSkinlib() {
     if ($('#skinlib-container').length != 0) {
         // Initially render skinlib
         requestSkinlibData().then(result => {
@@ -20,29 +44,7 @@ $(document).ready(() => {
             );
         });
     }
-});
-
-$('select.pagination').on('change', function () {
-    onPageChange(parseInt($(this).val()));
-});
-
-$('.filter').click(updateFilter);
-
-$('.sort').click(function (e) {
-    e.preventDefault();
-    $.skinlib.sort = $(this).data('sort');
-
-    console.log('Sort by ' + $.skinlib.sort);
-    reloadSkinlib();
-});
-
-$('#search-form').submit(function (e) {
-    e.preventDefault();
-    $.skinlib.keyword = $('#navbar-search-input').val();
-
-    console.log('Search keyword: ' + $.skinlib.keyword);
-    reloadSkinlib();
-});
+}
 
 function renderSkinlib(items) {
     let container = $('#skinlib-container').html('');
@@ -228,6 +230,7 @@ function updateBreadCrumb() {
 
 if (typeof require !== 'undefined' && typeof module !== 'undefined') {
     module.exports = {
+        initSkinlib,
         renderSkinlib,
         reloadSkinlib,
         updatePaginator,
diff --git a/resources/assets/src/js/skinlib/operations.js b/resources/assets/src/js/skinlib/operations.js
index 32b8aa16..4aa41b9e 100644
--- a/resources/assets/src/js/skinlib/operations.js
+++ b/resources/assets/src/js/skinlib/operations.js
@@ -1,6 +1,8 @@
 'use strict';
 
-$(document).on('click', '.more.like', function () {
+$(document).on('click', '.more.like', toggleLiked);
+
+function toggleLiked() {
     let tid = $(this).attr('tid');
 
     if ($(this).hasClass('anonymous'))
@@ -11,7 +13,7 @@ $(document).on('click', '.more.like', function () {
     } else {
         addToCloset(tid);
     }
-});
+}
 
 function addToCloset(tid) {
     $.getJSON(url(`skinlib/info/${tid}`), async ({ name }) => {
@@ -222,6 +224,7 @@ async function deleteTexture(tid) {
 
 if (typeof require !== 'undefined' && typeof module !== 'undefined') {
     module.exports = {
+        toggleLiked,
         addToCloset,
         changePrivacy,
         deleteTexture,
diff --git a/resources/assets/src/js/skinlib/upload.js b/resources/assets/src/js/skinlib/upload.js
index 15d92823..9977ba95 100644
--- a/resources/assets/src/js/skinlib/upload.js
+++ b/resources/assets/src/js/skinlib/upload.js
@@ -1,5 +1,7 @@
 /* global MSP */
 
+// TODO: Help wanted. This file needs to be tested.
+
 'use strict';
 
 $('body')