diff --git a/js/src/database/query_generator.ts b/js/src/database/query_generator.ts
index be0f684b30..4e165ac86c 100644
--- a/js/src/database/query_generator.ts
+++ b/js/src/database/query_generator.ts
@@ -45,7 +45,7 @@ function generateCondition (criteriaDiv, table) {
     return query;
 }
 
-window.generateWhereBlock = function () {
+function generateWhereBlock () {
     var count = 0;
     var query = '';
     $('.tableNameSelect').each(function () {
@@ -66,7 +66,7 @@ window.generateWhereBlock = function () {
     });
 
     return query;
-};
+}
 
 function generateJoin (newTable, tableAliases, fk) {
     var query = '';
@@ -126,7 +126,7 @@ function appendTable (table, tableAliases, usedTables, foreignKeys) {
     return query;
 }
 
-window.generateFromBlock = (tableAliases, foreignKeys) => {
+function generateFromBlock (tableAliases, foreignKeys) {
     var usedTables = [];
     var query = '';
     for (var table in tableAliases) {
@@ -136,4 +136,14 @@ window.generateFromBlock = (tableAliases, foreignKeys) => {
     }
 
     return query;
-};
+}
+
+declare global {
+    interface Window {
+        generateWhereBlock: typeof generateWhereBlock;
+        generateFromBlock: typeof generateFromBlock;
+    }
+}
+
+window.generateWhereBlock = generateWhereBlock;
+window.generateFromBlock = generateFromBlock;
diff --git a/js/src/designer/database.ts b/js/src/designer/database.ts
index ab958d8880..8e2ea0c141 100644
--- a/js/src/designer/database.ts
+++ b/js/src/designer/database.ts
@@ -14,8 +14,6 @@ var designerTables = [
 ];
 
 var DesignerOfflineDB = (function () {
-    var designerDB: {[k: string]: any} = {};
-
     /**
      * @type {IDBDatabase|null}
      */
@@ -25,7 +23,7 @@ var DesignerOfflineDB = (function () {
      * @param {string} table
      * @return {IDBTransaction}
      */
-    designerDB.getTransaction = function (table) {
+    const getTransaction = function (table) {
         return datastore.transaction([table], 'readwrite');
     };
 
@@ -33,7 +31,7 @@ var DesignerOfflineDB = (function () {
      * @param {string} table
      * @return {IDBObjectStore}
      */
-    designerDB.getObjectStore = function (table) {
+    const getObjectStore = function (table) {
         var transaction = designerDB.getTransaction(table);
         var objStore = transaction.objectStore(table);
 
@@ -45,7 +43,7 @@ var DesignerOfflineDB = (function () {
      * @param {string} table
      * @return {IDBObjectStore}
      */
-    designerDB.getCursorRequest = function (transaction, table) {
+    const getCursorRequest = function (transaction, table) {
         var objStore = transaction.objectStore(table);
         var keyRange = IDBKeyRange.lowerBound(0);
         var cursorRequest = objStore.openCursor(keyRange);
@@ -56,7 +54,7 @@ var DesignerOfflineDB = (function () {
     /**
      * @param {Function} callback
      */
-    designerDB.open = function (callback): void {
+    const open = function (callback): void {
         var version = 1;
         var request = window.indexedDB.open('pma_designer', version);
 
@@ -96,7 +94,7 @@ var DesignerOfflineDB = (function () {
      * @param {string} id
      * @param {Function} callback
      */
-    designerDB.loadObject = function (table, id, callback): void {
+    const loadObject = function (table, id, callback): void {
         if (datastore === null) {
             ajaxShowMessage(window.Messages.strIndexedDBNotWorking, null, 'error');
 
@@ -117,7 +115,7 @@ var DesignerOfflineDB = (function () {
      * @param {string} table
      * @param {Function} callback
      */
-    designerDB.loadAllObjects = function (table, callback): void {
+    const loadAllObjects = function (table, callback): void {
         if (datastore === null) {
             ajaxShowMessage(window.Messages.strIndexedDBNotWorking, null, 'error');
 
@@ -149,7 +147,7 @@ var DesignerOfflineDB = (function () {
      * @param {string} table
      * @param {Function} callback
      */
-    designerDB.loadFirstObject = function (table, callback): void {
+    const loadFirstObject = function (table, callback): void {
         if (datastore === null) {
             ajaxShowMessage(window.Messages.strIndexedDBNotWorking, null, 'error');
 
@@ -181,7 +179,7 @@ var DesignerOfflineDB = (function () {
      * @param {Object} obj
      * @param {Function} callback
      */
-    designerDB.addObject = function (table, obj, callback): void {
+    const addObject = function (table, obj, callback = undefined): void {
         if (datastore === null) {
             ajaxShowMessage(window.Messages.strIndexedDBNotWorking, null, 'error');
 
@@ -205,7 +203,7 @@ var DesignerOfflineDB = (function () {
      * @param {string} id
      * @param {Function} callback
      */
-    designerDB.deleteObject = function (table, id, callback): void {
+    const deleteObject = function (table, id, callback = undefined): void {
         if (datastore === null) {
             ajaxShowMessage(window.Messages.strIndexedDBNotWorking, null, 'error');
 
@@ -227,11 +225,24 @@ var DesignerOfflineDB = (function () {
     /**
      * @param {Error} e
      */
-    designerDB.onerror = function (e): void {
+    const onerror = function (e): void {
         // eslint-disable-next-line no-console
         console.log(e);
     };
 
+    var designerDB = {
+        getTransaction: getTransaction,
+        getObjectStore: getObjectStore,
+        getCursorRequest: getCursorRequest,
+        open: open,
+        loadObject: loadObject,
+        loadAllObjects: loadAllObjects,
+        loadFirstObject: loadFirstObject,
+        addObject: addObject,
+        deleteObject: deleteObject,
+        onerror: onerror,
+    };
+
     // Export the designerDB object.
     return designerDB;
 }());
diff --git a/js/src/designer/page.ts b/js/src/designer/page.ts
index 24b8935a9b..869b5bcc15 100644
--- a/js/src/designer/page.ts
+++ b/js/src/designer/page.ts
@@ -6,9 +6,7 @@ import { DesignerOfflineDB } from './database.ts';
 import { DesignerMove } from './move.ts';
 import { DesignerObjects } from './objects.ts';
 
-var DesignerPage = {};
-
-DesignerPage.showTablesInLandingPage = function (db) {
+function showTablesInLandingPage (db) {
     DesignerPage.loadFirstPage(db, function (page) {
         if (page) {
             DesignerPage.loadHtmlForPage(page.pgNr);
@@ -17,9 +15,9 @@ DesignerPage.showTablesInLandingPage = function (db) {
             DesignerPage.showNewPageTables(true);
         }
     });
-};
+}
 
-DesignerPage.saveToNewPage = function (db, pageName, tablePositions, callback) {
+function saveToNewPage (db, pageName, tablePositions, callback) {
     DesignerPage.createNewPage(db, pageName, function (page) {
         if (page) {
             var tblCords = [];
@@ -41,9 +39,9 @@ DesignerPage.saveToNewPage = function (db, pageName, tablePositions, callback) {
             }
         }
     });
-};
+}
 
-DesignerPage.saveToSelectedPage = function (db, pageId, pageName, tablePositions, callback) {
+function saveToSelectedPage (db, pageId, pageName, tablePositions, callback) {
     DesignerPage.deletePage(pageId);
     DesignerPage.saveToNewPage(db, pageName, tablePositions, function (page) {
         if (typeof callback !== 'undefined') {
@@ -52,9 +50,9 @@ DesignerPage.saveToSelectedPage = function (db, pageId, pageName, tablePositions
 
         DesignerConfig.selectedPage = page.pgNr;
     });
-};
+}
 
-DesignerPage.createNewPage = function (db, pageName, callback) {
+function createNewPage (db, pageName, callback) {
     var newPage = new DesignerObjects.PdfPage(db, pageName, []);
     DesignerOfflineDB.addObject('pdf_pages', newPage, function (pgNr) {
         newPage.pgNr = pgNr;
@@ -62,13 +60,13 @@ DesignerPage.createNewPage = function (db, pageName, callback) {
             callback(newPage);
         }
     });
-};
+}
 
-DesignerPage.saveTablePositions = function (positions, callback) {
+function saveTablePositions (positions, callback) {
     DesignerOfflineDB.addObject('table_coords', positions, callback);
-};
+}
 
-DesignerPage.createPageList = function (db, callback) {
+function createPageList (db, callback) {
     DesignerOfflineDB.loadAllObjects('pdf_pages', function (pages) {
         var html = '';
         for (var p = 0; p < pages.length; p++) {
@@ -83,9 +81,9 @@ DesignerPage.createPageList = function (db, callback) {
             callback(html);
         }
     });
-};
+}
 
-DesignerPage.deletePage = function (pageId, callback) {
+function deletePage (pageId, callback = undefined) {
     DesignerOfflineDB.loadObject('pdf_pages', pageId, function (page) {
         if (page) {
             for (var i = 0; i < page.tblCords.length; i++) {
@@ -95,9 +93,9 @@ DesignerPage.deletePage = function (pageId, callback) {
             DesignerOfflineDB.deleteObject('pdf_pages', pageId, callback);
         }
     });
-};
+}
 
-DesignerPage.loadFirstPage = function (db, callback) {
+function loadFirstPage (db, callback) {
     DesignerOfflineDB.loadAllObjects('pdf_pages', function (pages) {
         var firstPage = null;
         for (var i = 0; i < pages.length; i++) {
@@ -118,10 +116,10 @@ DesignerPage.loadFirstPage = function (db, callback) {
 
         callback(firstPage);
     });
-};
+}
 
-DesignerPage.showNewPageTables = function (check) {
-    var allTables = $('#id_scroll_tab').find('td input:checkbox');
+function showNewPageTables (check) {
+    var allTables = ($('#id_scroll_tab').find('td input:checkbox') as JQuery<HTMLInputElement>);
     allTables.prop('checked', check);
     for (var tab = 0; tab < allTables.length; tab++) {
         var input = allTables[tab];
@@ -136,9 +134,9 @@ DesignerPage.showNewPageTables = function (check) {
     DesignerConfig.selectedPage = -1;
     $('#page_name').text(window.Messages.strUntitled);
     DesignerMove.markUnsaved();
-};
+}
 
-DesignerPage.loadHtmlForPage = function (pageId) {
+function loadHtmlForPage (pageId) {
     DesignerPage.showNewPageTables(true);
     DesignerPage.loadPageObjects(pageId, function (page, tblCords) {
         $('#name-panel').find('#page_name').text(page.pageDescr);
@@ -154,7 +152,7 @@ DesignerPage.loadHtmlForPage = function (pageId) {
             table.style.top = tblCords[t].y + 'px';
             table.style.left = tblCords[t].x + 'px';
 
-            var checkbox = document.getElementById('check_vis_' + tbId);
+            var checkbox = (document.getElementById('check_vis_' + tbId) as HTMLInputElement);
             checkbox.checked = true;
             DesignerMove.visibleTab(checkbox, checkbox.value);
         }
@@ -167,9 +165,9 @@ DesignerPage.loadHtmlForPage = function (pageId) {
 
         DesignerConfig.selectedPage = page.pgNr;
     });
-};
+}
 
-DesignerPage.loadPageObjects = function (pageId, callback) {
+function loadPageObjects (pageId, callback) {
     DesignerOfflineDB.loadObject('pdf_pages', pageId, function (page) {
         var tblCords = [];
         var count = page.tblCords.length;
@@ -184,12 +182,27 @@ DesignerPage.loadPageObjects = function (pageId, callback) {
             });
         }
     });
-};
+}
 
-DesignerPage.getRandom = function (max, min) {
+function getRandom (max, min) {
     var val = Math.random() * (max - min) + min;
 
     return Math.floor(val);
+}
+
+const DesignerPage = {
+    showTablesInLandingPage: showTablesInLandingPage,
+    saveToNewPage: saveToNewPage,
+    saveToSelectedPage: saveToSelectedPage,
+    createNewPage: createNewPage,
+    saveTablePositions: saveTablePositions,
+    createPageList: createPageList,
+    deletePage: deletePage,
+    loadFirstPage: loadFirstPage,
+    showNewPageTables: showNewPageTables,
+    loadHtmlForPage: loadHtmlForPage,
+    loadPageObjects: loadPageObjects,
+    getRandom: getRandom,
 };
 
 export { DesignerPage };
diff --git a/js/src/jquery.sortable-table.ts b/js/src/jquery.sortable-table.ts
index 990f529708..cfc4439d06 100644
--- a/js/src/jquery.sortable-table.ts
+++ b/js/src/jquery.sortable-table.ts
@@ -278,7 +278,7 @@ import $ from 'jquery';
                 previewMove = null;
             }
 
-            function moveTo (elem, opts = {}) {
+            function moveTo (elem, opts: {pos?: any, duration?: any} = {}) {
                 if (! opts.pos) {
                     opts.pos = { left: 0, top: 0 };
                 }
diff --git a/js/src/modules/config.ts b/js/src/modules/config.ts
index aaf99cbf3f..a3d82eff07 100644
--- a/js/src/modules/config.ts
+++ b/js/src/modules/config.ts
@@ -801,7 +801,7 @@ function on () {
             if (! lsSupported) {
                 disabled = $form.find('input[type=radio][value$=local_storage]').prop('checked');
             } else if (! lsExists && $form.attr('name') === 'prefs_import' &&
-                $('#import_local_storage')[0].checked
+                ($('#import_local_storage') as JQuery<HTMLInputElement>)[0].checked
             ) {
                 disabled = true;
             }
diff --git a/js/src/modules/navigation.ts b/js/src/modules/navigation.ts
index 17a8660d1c..d303f8939d 100644
--- a/js/src/modules/navigation.ts
+++ b/js/src/modules/navigation.ts
@@ -624,7 +624,7 @@ function ensureSettings (selflink): void {
  * @param {object} paths stored navigation paths
  */
 function reload (callback = null, paths = null): void {
-    var params = {
+    var params: { server: any; reload: boolean; no_debug: boolean, db?: string } = {
         'reload': true,
         'no_debug': true,
         'server': CommonParams.get('server'),
@@ -1070,8 +1070,7 @@ const FastFilter = {
      */
     getSearchClause: function () {
         var retval = '';
-        var $input = $('#pma_navigation_tree')
-            .find('li.fast_filter.db_fast_filter input.searchClause');
+        var $input = ($('#pma_navigation_tree').find('li.fast_filter.db_fast_filter input.searchClause') as JQuery<HTMLInputElement>);
         if ($input.length && $input.val() !== $input[0].defaultValue) {
             retval = $input.val();
         }
@@ -1278,7 +1277,7 @@ FastFilter.Filter.prototype.request = function (): void {
     var params = self.$this.find('> ul > li > form.fast_filter').first().serialize();
 
     if (self.$this.find('> ul > li > form.fast_filter').first().find('input[name=searchClause]').length === 0) {
-        var $input = $('#pma_navigation_tree').find('li.fast_filter.db_fast_filter input.searchClause');
+        var $input = ($('#pma_navigation_tree').find('li.fast_filter.db_fast_filter input.searchClause') as JQuery<HTMLInputElement>);
         if ($input.length && $input.val() !== $input[0].defaultValue) {
             params += CommonParams.get('arg_separator') + 'searchClause=' + encodeURIComponent($input.val());
         }
diff --git a/js/src/name-conflict-fixes.ts b/js/src/name-conflict-fixes.ts
index 8202aba9c0..834556669f 100644
--- a/js/src/name-conflict-fixes.ts
+++ b/js/src/name-conflict-fixes.ts
@@ -1,3 +1,4 @@
 import $ from 'jquery';
 
+// @ts-ignore
 $.widget.bridge('uiTooltip', $.ui.tooltip);
diff --git a/js/src/setup/scripts.ts b/js/src/setup/scripts.ts
index 596f005917..7a8fe5b7be 100644
--- a/js/src/setup/scripts.ts
+++ b/js/src/setup/scripts.ts
@@ -102,8 +102,10 @@ function ajaxValidate (parent, id, values) {
 
             var error = {};
             if (typeof response !== 'object') {
+                // @ts-ignore
                 error[$parent.id] = [response];
             } else if (typeof response.error !== 'undefined') {
+                // @ts-ignore
                 error[$parent.id] = [response.error];
             } else {
                 for (var key in response) {
@@ -189,6 +191,7 @@ $.extend(true, window.validators, {
          * @return {true}
          */
         Server_login_options: function (isKeyUp) { // eslint-disable-line camelcase
+            // @ts-ignore
             return window.validators.fieldset.Server.apply(this, [isKeyUp]);
         },
         /**
diff --git a/js/src/table/zoom_plot_jqplot.ts b/js/src/table/zoom_plot_jqplot.ts
index 757e7c0700..0156a0c491 100644
--- a/js/src/table/zoom_plot_jqplot.ts
+++ b/js/src/table/zoom_plot_jqplot.ts
@@ -28,6 +28,7 @@ function displayHelp () {
  * @param {number[]} array
  * @return {number}
  **/
+// @ts-ignore
 Array.max = function (array) {
     return Math.max.apply(Math, array);
 };
@@ -37,6 +38,7 @@ Array.max = function (array) {
  * @param {number[]} array
  * @return {number}
  **/
+// @ts-ignore
 Array.min = function (array) {
     return Math.min.apply(Math, array);
 };