diff --git a/gulpfile.js b/gulpfile.js
index 45ff96ed..bfcf498a 100644
--- a/gulpfile.js
+++ b/gulpfile.js
@@ -1,8 +1,6 @@
 var gulp = require('gulp');
 var file = require('gulp-file');
 
-var ts = require('gulp-typescript');
-var tsProject = ts.createProject('tsconfig.json');
 var jsonfile = require('jsonfile')
 var ghPages = require('gulp-gh-pages');
 var replace = require('gulp-replace');
@@ -21,45 +19,36 @@ gulp.task('demos', function () {
         .pipe(gulp.dest('build/demos'));
 });
 
-gulp.task('build', function () {
+gulp.task('compile', function () {
     return gulp
         .src([
-            'src/lib/**/*.tsx',
-            '!src/**/*.test.tsx',
-            'src/lib/**/*.ts',
-            '!src/**/*.test.ts',
+            'README.md',
+            'LICENSE',
         ])
         .pipe(gulp.dest('dist'))
-        .pipe(tsProject())
-        .pipe(gulp.dest('dist'))
         .on('end', () => {
             var pkg = require('./package.json');
             delete pkg.dependencies;
             delete pkg.devDependencies;
+            delete pkg.scripts;
             delete pkg.husky;
             delete pkg.jest;
             var outputFile = 'dist/package.json';
             file(outputFile, '');
             jsonfile.writeFile('dist/package.json', pkg, { spaces: 2 });
-            gulp
-                .src([
-                    'README.md',
-                    'LICENSE',
-                ])
-                .pipe(gulp.dest('dist'));
             gulp
                 .src([
                     'src/lib/**/*.scss'
                 ])
                 .pipe(gulp.dest('dist'))
                 .on('end', () => {
-                    gulp.src('dist/**/*.scss')
+                    gulp.src('dist/*.scss')
                         .pipe(sass().on('error', sass.logError))
                         .pipe(gulp.dest('dist'));
                 });
             gulp
                 .src([
-                    'src/lib/static/**/*'
+                    'src/lib/static/*'
                 ])
                 .pipe(gulp.dest('dist/static'))
         });
diff --git a/package.json b/package.json
index 40ede46f..6c53186e 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "ka-table",
-  "version": "5.5.1",
+  "version": "6.0.0",
   "license": "MIT",
   "repository": "github:komarovalexander/ka-table",
   "homepage": "https://komarovalexander.github.io/ka-table/#/overview",
@@ -33,7 +33,7 @@
     "coveralls": "cat ./coverage/lcov.info | node node_modules/.bin/coveralls",
     "dist": "tsc --declaration --jsx react --esModuleInterop true --outDir dist src/lib/index.ts && gulp build",
     "pack": "gulp build && cd dist && npm pack && cd ..",
-    "compile": "tsc src/lib/index.ts --jsx react --esModuleInterop true --outDir dist --declaration true --target es5"
+    "compile": "tsc src/lib/index.ts --jsx react --esModuleInterop true --outDir dist --declaration true --target es5 && gulp compile"
   },
   "eslintConfig": {
     "extends": "react-app"
@@ -65,7 +65,6 @@
     "gulp-gh-pages": "^0.5.4",
     "gulp-replace": "^1.0.0",
     "gulp-sass": "^4.0.2",
-    "gulp-typescript": "^5.0.1",
     "jsonfile": "^6.0.1",
     "node-sass": "^4.13.1",
     "react-filter-control": "^2.1.0",
@@ -86,6 +85,12 @@
   },
   "keywords": [
     "datagrid",
+    "ts",
+    "js",
+    "javascript",
+    "typescript",
+    "datatable",
+    "ui-component",
     "react",
     "table",
     "component",
diff --git a/src/Demos/BootstrapDemo/customHooks.ts b/src/Demos/BootstrapDemo/customHooks.ts
deleted file mode 100644
index 0d8ed1f3..00000000
--- a/src/Demos/BootstrapDemo/customHooks.ts
+++ /dev/null
@@ -1,29 +0,0 @@
-import { useEffect, useRef } from 'react';
-
-export function useOuterClick(callback: any) {
-  const innerRef = useRef<any>();
-  const callbackRef = useRef<any>();
-
-  // set current callback in ref, before second useEffect uses it
-  useEffect(() => { // useEffect wrapper to be safe for concurrent mode
-    callbackRef.current = callback;
-  });
-
-  useEffect(() => {
-    document.addEventListener('click', handleClick);
-    return () => document.removeEventListener('click', handleClick);
-
-    // read most recent callback and innerRef dom node from refs
-    function handleClick(e: any) {
-      if (
-        innerRef.current &&
-        callbackRef.current &&
-        !innerRef.current.contains(e.target)
-      ) {
-        callbackRef.current(e);
-      }
-    }
-  }, []); // no need for callback + innerRef dep
-
-  return innerRef; // return ref; client can omit `useRef`
-}
\ No newline at end of file
diff --git a/src/Demos/BootstrapDemo/editors.tsx b/src/Demos/BootstrapDemo/editors.tsx
index 45e6fc23..10bfc711 100644
--- a/src/Demos/BootstrapDemo/editors.tsx
+++ b/src/Demos/BootstrapDemo/editors.tsx
@@ -33,7 +33,7 @@ export const CustomLookupEditor: React.FC<IFilterRowEditorProps> = ({
   );
 };
 
-export const FilterOperators: React.FC<{ column: Column; dispatch: DispatchFunc }> = ({
+const FilterOperators: React.FC<{ column: Column; dispatch: DispatchFunc }> = ({
   column, dispatch,
 }) => {
   return (
diff --git a/src/Demos/CustomDataRowDemo/CustomDataRowDemo.tsx b/src/Demos/CustomDataRowDemo/CustomDataRowDemo.tsx
index 2e3f27ee..06dc3790 100644
--- a/src/Demos/CustomDataRowDemo/CustomDataRowDemo.tsx
+++ b/src/Demos/CustomDataRowDemo/CustomDataRowDemo.tsx
@@ -1,6 +1,7 @@
 import React, { useState } from 'react';
 
 import { ITableProps, kaReducer, Table } from '../../lib';
+import defaultOptions from '../../lib/defaultOptions';
 import { DataType, SortDirection, SortingMode } from '../../lib/enums';
 import { IDataRowProps } from '../../lib/props';
 import { DispatchFunc } from '../../lib/types';
@@ -14,11 +15,13 @@ const dataArray: any[] = [
   { id: 6, name: 'Sunny Fox', score: 33, passed: false },
 ];
 
-const DataRow: React.FC<IDataRowProps> = ({rowData}) => {
+const DataRow: React.FC<IDataRowProps> = ({rowData, columns}) => {
   return (
-    <div>
-      {rowData.name}: {rowData.score} ({rowData.passed ? 'Passed' : 'Failed'})
-    </div>
+    <td className={defaultOptions.css.cell} colSpan={columns.length}>
+      <div>
+        {rowData.name}: {rowData.score} ({rowData.passed ? 'Passed' : 'Failed'})
+      </div>
+    </td>
   );
 };
 
diff --git a/src/Demos/Demo.ts b/src/Demos/Demo.ts
index c62ea7aa..67781a72 100644
--- a/src/Demos/Demo.ts
+++ b/src/Demos/Demo.ts
@@ -7,8 +7,7 @@ export default class Demo {
     public fileName: string,
     public jsLink: string = '',
     public tsLink: string = '',
-    public group: string = '',
-    public disableOnlineEditor: boolean = false) {
+    public group: string = '') {
       this.jsLink = jsLink + '?file=Demo.js';
       this.tsLink = tsLink + '?file=Demo.tsx';
   }
diff --git a/src/Demos/DemoPage.tsx b/src/Demos/DemoPage.tsx
index 255f5d2b..0e140e01 100644
--- a/src/Demos/DemoPage.tsx
+++ b/src/Demos/DemoPage.tsx
@@ -18,18 +18,14 @@ const getDemoPage = (demo: Demo) => {
         <div className='code'>
           <div className='editor-links'>
             <span>Open in Online Editor: </span>
-            {demo.disableOnlineEditor || (
-              <>
-                <a className='editor-link editor-link-ts'
-                  href={demo.tsLink}
-                  onMouseDown={() => { trackEvent('click', 'ts_example', demo.path); }}
-                  rel='noopener noreferrer'
-                  target='_blank'>
-                    TS Example
-                </a>
-                <span>|</span>
-              </>
-            )}
+            <a className='editor-link editor-link-ts'
+              href={demo.tsLink}
+              onMouseDown={() => { trackEvent('click', 'ts_example', demo.path); }}
+              rel='noopener noreferrer'
+              target='_blank'>
+                TS Example
+            </a>
+            <span>|</span>
             <a className='editor-link editor-link-js'
               href={demo.jsLink}
               onMouseDown={() => { trackEvent('click', 'js_example', demo.path); }}
diff --git a/src/Demos/Demos.tsx b/src/Demos/Demos.tsx
index bbe6665a..47c544bf 100644
--- a/src/Demos/Demos.tsx
+++ b/src/Demos/Demos.tsx
@@ -41,6 +41,7 @@ import LoadingDemo from './LoadingDemo/LoadingDemo';
 import ManyColumnsDemo from './ManyColumnsDemo/ManyColumnsDemo';
 import ManyRowsDemo from './ManyRowsDemo/ManyRowsDemo';
 import ManyRowsGroupingDemo from './ManyRowsGroupingDemo/ManyRowsGroupingDemo';
+import ManyRowsMemoDemo from './ManyRowsMemoDemo/ManyRowsMemoDemo';
 import MaterialDemo from './MaterialDemo/MaterialDemo';
 import NullableCellDataDemo from './NullableCellDataDemo/NullableCellDataDemo';
 import OverviewDemo from './OverviewDemo/OverviewDemo';
@@ -85,15 +86,16 @@ const demos: Demo[] = [
   new Demo(FilterRowCustomEditorDemo, '/filter-row-custom-editor', 'Filter Row - Custom Editor', 'FilterRowCustomEditorDemo', 'https://stackblitz.com/edit/table-filter-row-custom-editor-js', 'https://stackblitz.com/edit/table-filter-row-custom-editor-ts', 'Filtering'),
   new Demo(FixedColumnDemo, '/fixed-column', 'Fixed Colum', 'FixedColumnDemo', 'https://stackblitz.com/edit/table-fixed-column-js', 'https://stackblitz.com/edit/table-fixed-column-ts', 'Columns'),
   new Demo(GetDataByPropsDemo, '/get-data-by-props', 'Get Data By Props', 'GetDataByPropsDemo', 'https://stackblitz.com/edit/table-get-data-by-props-js', 'https://stackblitz.com/edit/table-get-data-by-props-ts', 'Miscellaneous'),
-  new Demo(GroupingDemo, '/grouping', 'Grouping', 'GroupingDemo', 'https://stackblitz.com/edit/table-grouping-js', 'https://stackblitz.com/edit/table-grouping-ts', 'Grouping', true),
-  new Demo(GroupingCustomCellDemo, '/grouping-custom-cell', 'Grouping Custom Cell', 'GroupingCustomCellDemo', 'https://stackblitz.com/edit/table-grouping-custom-cell-js', 'https://stackblitz.com/edit/table-grouping-custom-cell-ts', 'Grouping', true),
-  new Demo(GroupingCustomRowDemo, '/grouping-custom-row', 'Grouping Custom Row', 'GroupingCustomRowDemo', 'https://stackblitz.com/edit/table-grouping-custom-row-js', 'https://stackblitz.com/edit/table-grouping-custom-row-ts', 'Grouping', true),
+  new Demo(GroupingDemo, '/grouping', 'Grouping', 'GroupingDemo', 'https://stackblitz.com/edit/table-grouping-js', 'https://stackblitz.com/edit/table-grouping-ts', 'Grouping'),
+  new Demo(GroupingCustomCellDemo, '/grouping-custom-cell', 'Grouping Custom Cell', 'GroupingCustomCellDemo', 'https://stackblitz.com/edit/table-grouping-custom-cell-js', 'https://stackblitz.com/edit/table-grouping-custom-cell-ts', 'Grouping'),
+  new Demo(GroupingCustomRowDemo, '/grouping-custom-row', 'Grouping Custom Row', 'GroupingCustomRowDemo', 'https://stackblitz.com/edit/table-grouping-custom-row-js', 'https://stackblitz.com/edit/table-grouping-custom-row-ts', 'Grouping'),
   new Demo(HoverRowDemo, '/hover-row', 'Hover Row', 'HoverRowDemo', 'https://stackblitz.com/edit/table-hover-row-js', 'https://stackblitz.com/edit/table-hover-row-ts', 'Rows'),
   new Demo(LoadingDemo, '/loading', 'Loading', 'LoadingDemo', 'https://stackblitz.com/edit/table-loading-js', 'https://stackblitz.com/edit/table-loading-ts', 'Miscellaneous'),
   new Demo(ManyColumnsDemo, '/many-columns', 'Many Columns', 'ManyColumnsDemo', 'https://stackblitz.com/edit/table-many-columns-js', 'https://stackblitz.com/edit/table-many-columns-ts', 'Columns'),
-  new Demo(ManyRowsDemo, '/many-rows', 'Many Rows (100k)', 'ManyRowsDemo', 'https://stackblitz.com/edit/table-many-rows-js', 'https://stackblitz.com/edit/table-many-rows-ts', 'Virtual Scrolling'),
-  new Demo(ManyRowsGroupingDemo, '/many-rows-grouping', 'Many Rows (10k Grouped)', 'ManyRowsGroupingDemo', 'https://stackblitz.com/edit/table-many-rows-grouping-js', 'https://stackblitz.com/edit/table-many-rows-grouping-ts', 'Virtual Scrolling', true),
-  new Demo(NullableCellDataDemo, '/nullable-cell-data', 'Nullable Cell Data', 'NullableCellDataDemo', 'https://stackblitz.com/edit/table-nullable-cell-data-js', 'https://stackblitz.com/edit/table-nullable-cell-data-ts', 'Miscellaneous', true),
+  new Demo(ManyRowsDemo, '/many-rows', '100K Rows', 'ManyRowsDemo', 'https://stackblitz.com/edit/table-many-rows-js', 'https://stackblitz.com/edit/table-many-rows-ts', 'Virtual Scrolling'),
+  new Demo(ManyRowsMemoDemo, '/many-rows-memo', '300K Rows & memo', 'ManyRowsMemoDemo', 'https://stackblitz.com/edit/table-many-rows-memo-js', 'https://stackblitz.com/edit/table-many-rows-memo-ts', 'Virtual Scrolling'),
+  new Demo(ManyRowsGroupingDemo, '/many-rows-grouping', '10k Grouped', 'ManyRowsGroupingDemo', 'https://stackblitz.com/edit/table-many-rows-grouping-js', 'https://stackblitz.com/edit/table-many-rows-grouping-ts', 'Virtual Scrolling'),
+  new Demo(NullableCellDataDemo, '/nullable-cell-data', 'Nullable Cell Data', 'NullableCellDataDemo', 'https://stackblitz.com/edit/table-nullable-cell-data-js', 'https://stackblitz.com/edit/table-nullable-cell-data-ts', 'Miscellaneous'),
   new Demo(PagingDemo, '/paging', 'Paging', 'PagingDemo', 'https://stackblitz.com/edit/table-paging-js', 'https://stackblitz.com/edit/table-paging-ts', 'Miscellaneous'),
   new Demo(PrintDemo, '/print', 'Print', 'PrintDemo', 'https://stackblitz.com/edit/table-print-js', 'https://stackblitz.com/edit/table-print-ts', 'Export / Print'),
   new Demo(ReduxDemo, '/redux', 'Redux', 'ReduxDemo', 'https://stackblitz.com/edit/table-redux-js', 'https://stackblitz.com/edit/table-redux-ts', ''),
@@ -103,7 +105,7 @@ const demos: Demo[] = [
   new Demo(SelectionDemo, '/selection', 'Selection - Multiple', 'SelectionDemo', 'https://stackblitz.com/edit/table-selection-js', 'https://stackblitz.com/edit/table-selection-ts', 'Selection'),
   new Demo(SelectionSingleDemo, '/selection-single', 'Selection - Single', 'SelectionSingleDemo', 'https://stackblitz.com/edit/table-selection-single-js', 'https://stackblitz.com/edit/table-selection-single-ts', 'Selection'),
   new Demo(SortingDemo, '/sorting', 'Sorting', 'SortingDemo', 'https://stackblitz.com/edit/table-sorting-js', 'https://stackblitz.com/edit/table-sorting-ts', ''),
-  new Demo(StateStoringDemo, '/state-storing', 'State Storing', 'StateStoringDemo', 'https://stackblitz.com/edit/table-state-storing-js', '', 'Miscellaneous', true),
+  new Demo(StateStoringDemo, '/state-storing', 'State Storing', 'StateStoringDemo', 'https://stackblitz.com/edit/table-state-storing-js', '', 'Miscellaneous'),
   new Demo(ValidationDemo, '/validation', 'Validation', 'ValidationDemo', 'https://stackblitz.com/edit/table-validation-js', 'https://stackblitz.com/edit/table-validation-ts', 'Editing'),
 ];
 
diff --git a/src/Demos/FilterExtendedDemo/FilterExtendedDemo.tsx b/src/Demos/FilterExtendedDemo/FilterExtendedDemo.tsx
index 83eb9ea9..fc6ce9fb 100644
--- a/src/Demos/FilterExtendedDemo/FilterExtendedDemo.tsx
+++ b/src/Demos/FilterExtendedDemo/FilterExtendedDemo.tsx
@@ -28,7 +28,7 @@ const tablePropsInit: ITableProps = {
   rowKeyField: 'id',
 };
 
-export const fields = [{
+const fields = [{
   caption: 'Name',
   name: 'name',
   operators: [{
@@ -56,14 +56,14 @@ export const fields = [{
   }],
 }];
 
-export const groups = [{
+const groups = [{
   caption: 'And',
   name: 'and',
 }, {
   caption: 'Or',
   name: 'or',
 }];
-export const filter: IFilterControlFilterValue = {
+const filter: IFilterControlFilterValue = {
   groupName: 'and',
   items: [
     {
diff --git a/src/Demos/FilterExtendedDemo/filterData.ts b/src/Demos/FilterExtendedDemo/filterData.ts
index 1301a51d..a7f2e999 100644
--- a/src/Demos/FilterExtendedDemo/filterData.ts
+++ b/src/Demos/FilterExtendedDemo/filterData.ts
@@ -1,5 +1,3 @@
-export const isEmpty = (value: any) => (value == null || value.length === 0);
-
 const contains = (data: any[], item: any) => {
   if (!item.value) { return true; }
   return data[item.field].toLowerCase().includes(item.value.toLowerCase());
@@ -18,7 +16,7 @@ const isNotEqual = (data: any[], item: any) => {
 };
 const more = (data: any[], item: any) => data[item.field] > item.value;
 const less = (data: any[], item: any) => data[item.field] < item.value;
-export const filterItem = (data: any[], filter: any) => {
+const filterItem = (data: any[], filter: any) => {
   switch (filter.operator) {
     case 'contains': return contains(data, filter);
     case 'doesNotContain': return doesNotContain(data, filter);
@@ -30,7 +28,7 @@ export const filterItem = (data: any[], filter: any) => {
   }
 };
 
-export const filterGroup = (data: any[], groupName: string, items: any[]): any[] =>
+const filterGroup = (data: any[], groupName: string, items: any[]): any[] =>
   (groupName.toLowerCase() === 'or' ? filterGroupOr(data, items) : filterGroupAnd(data, items));
 
 export const filterGroupOr = (data: any[], items: any[]): any[]  => {
diff --git a/src/Demos/ManyRowsDemo/ManyRowsDemo.tsx b/src/Demos/ManyRowsDemo/ManyRowsDemo.tsx
index 9b6e2185..6a6925fa 100644
--- a/src/Demos/ManyRowsDemo/ManyRowsDemo.tsx
+++ b/src/Demos/ManyRowsDemo/ManyRowsDemo.tsx
@@ -38,6 +38,11 @@ const ManyRowsDemo: React.FC = () => {
     <Table
       {...tableProps}
       dispatch={dispatch}
+      childComponents={{
+        tableWrapper: {
+          elementAttributes: () => ({ style: { maxHeight: 600 }})
+        }
+      }}
     />
   );
 };
diff --git a/src/Demos/ManyRowsGroupingDemo/ManyRowsGroupingDemo.tsx b/src/Demos/ManyRowsGroupingDemo/ManyRowsGroupingDemo.tsx
index f64bc6dc..6ba0834d 100644
--- a/src/Demos/ManyRowsGroupingDemo/ManyRowsGroupingDemo.tsx
+++ b/src/Demos/ManyRowsGroupingDemo/ManyRowsGroupingDemo.tsx
@@ -40,6 +40,11 @@ const ManyRowsGroupingDemo: React.FC = () => {
     <Table
       {...tableProps}
       dispatch={dispatch}
+      childComponents={{
+        tableWrapper: {
+          elementAttributes: () => ({ style: { maxHeight: 600 }})
+        }
+      }}
     />
   );
 };
diff --git a/src/Demos/ManyRowsMemoDemo/ManyRowsMemoDemo.test.tsx b/src/Demos/ManyRowsMemoDemo/ManyRowsMemoDemo.test.tsx
new file mode 100644
index 00000000..c830f9b8
--- /dev/null
+++ b/src/Demos/ManyRowsMemoDemo/ManyRowsMemoDemo.test.tsx
@@ -0,0 +1,10 @@
+import React from 'react';
+import ReactDOM from 'react-dom';
+
+import ManyRowsMemoDemo from './ManyRowsMemoDemo';
+
+it('renders without crashing', () => {
+  const div = document.createElement('div');
+  ReactDOM.render(<ManyRowsMemoDemo />, div);
+  ReactDOM.unmountComponentAtNode(div);
+});
diff --git a/src/Demos/ManyRowsMemoDemo/ManyRowsMemoDemo.tsx b/src/Demos/ManyRowsMemoDemo/ManyRowsMemoDemo.tsx
new file mode 100644
index 00000000..7ea4c071
--- /dev/null
+++ b/src/Demos/ManyRowsMemoDemo/ManyRowsMemoDemo.tsx
@@ -0,0 +1,66 @@
+import React, { useState } from 'react';
+
+import { ITableProps, kaReducer, Table } from '../../lib';
+import DataRowContent from '../../lib/Components/DataRowContent/DataRowContent';
+import { DataType } from '../../lib/enums';
+import { IDataRowProps } from '../../lib/props';
+import { DispatchFunc } from '../../lib/types';
+
+let dataArray: any[];
+
+const getDataArray = () => {
+  if (!dataArray){
+    dataArray = Array(300000).fill(undefined).map(
+      (_, index) => ({
+        column1: `column:1 row:${index}`,
+        column2: `column:2 row:${index}`,
+        column3: `column:3 row:${index}`,
+        column4: `column:4 row:${index}`,
+        id: index,
+      }),
+    );
+  }
+  return dataArray;
+};
+
+const tablePropsInit: ITableProps = {
+  columns: [
+    { key: 'column1', title: 'Column 1', dataType: DataType.String },
+    { key: 'column2', title: 'Column 2', dataType: DataType.String },
+    { key: 'column3', title: 'Column 3', dataType: DataType.String },
+    { key: 'column4', title: 'Column 4', dataType: DataType.String },
+  ],
+  rowKeyField: 'id',
+  virtualScrolling: {
+    enabled: true
+  },
+};
+
+const DataRowContentMemo = React.memo((props: IDataRowProps) => <DataRowContent {...props}/>, () => true);
+
+const ManyRowsMemoDemo: React.FC = () => {
+  const [tableProps, changeTableProps] = useState({ ...tablePropsInit, data: getDataArray() });
+  const dispatch: DispatchFunc = (action) => {
+    changeTableProps((prevState: ITableProps) => kaReducer(prevState, action));
+  };
+
+  return (
+    <Table
+      {...tableProps}
+      dispatch={dispatch}
+      childComponents={{
+        cellText: {
+          elementAttributes: () => ({ style: {lineHeight: '25px'} }),
+        },
+        dataRow: {
+          content: (props: IDataRowProps) => <DataRowContentMemo {...props}/>
+        },
+        tableWrapper: {
+          elementAttributes: () => ({ style: { maxHeight: 600 }})
+        }
+      }}
+    />
+  );
+};
+
+export default ManyRowsMemoDemo;
diff --git a/src/Demos/MaterialDemo/editors.tsx b/src/Demos/MaterialDemo/editors.tsx
deleted file mode 100644
index 45e6fc23..00000000
--- a/src/Demos/MaterialDemo/editors.tsx
+++ /dev/null
@@ -1,93 +0,0 @@
-import React from 'react';
-
-import { updateFilterRowOperator, updateFilterRowValue } from '../../lib/actionCreators';
-import { Column } from '../../lib/models';
-import { IFilterRowEditorProps } from '../../lib/props';
-import { DispatchFunc } from '../../lib/types';
-import { kaDateUtils } from '../../lib/utils';
-
-export const CustomLookupEditor: React.FC<IFilterRowEditorProps> = ({
-  column, dispatch,
-}) => {
-  const toNullableBoolean = (value: any) => {
-    switch (value) {
-      case 'true': return true;
-      case 'false': return false;
-    }
-    return value;
-  };
-  return (
-    <>
-      <select
-        className='form-control'
-        defaultValue={column.filterRowValue}
-        style={{width: 100}}
-        onChange={(event) => {
-          dispatch(updateFilterRowValue(column.key, toNullableBoolean(event.currentTarget.value)));
-        }}>
-        <option value=''/>
-        <option value={'true'}>True</option>
-        <option value={'false'}>False</option>
-      </select>
-    </>
-  );
-};
-
-export const FilterOperators: React.FC<{ column: Column; dispatch: DispatchFunc }> = ({
-  column, dispatch,
-}) => {
-  return (
-    <select
-      className='form-control'
-      defaultValue={column.filterRowOperator}
-      onChange={(event) => {
-        dispatch(updateFilterRowOperator(column.key, event.currentTarget.value));
-      }}>
-      <option value={'='}>=</option>
-      <option value={'<'}>{'<'}</option>
-      <option value={'>'}>{'>'}</option>
-      <option value={'<='}>{'<='}</option>
-      <option value={'>='}>{'>='}</option>
-    </select>
-  );
-};
-
-export const NumberEditor: React.FC<IFilterRowEditorProps> = ({
-  column, dispatch,
-}) => {
-  return (
-    <>
-      <FilterOperators column={column} dispatch={dispatch}/>
-      <input
-        defaultValue={column.filterRowValue}
-        style={{width: 100}}
-        onChange={(event) => {
-          const filterRowValue = event.currentTarget.value !== '' ? Number(event.currentTarget.value) : null;
-          dispatch(updateFilterRowValue(column.key, filterRowValue));
-        }}
-        type='number'
-      />
-    </>
-  );
-};
-
-export const DateEditor: React.FC<IFilterRowEditorProps> = ({
-  column, dispatch,
-}) => {
-  const fieldValue = column.filterRowValue;
-  const value = fieldValue && kaDateUtils.getDateInputValue(fieldValue);
-  return (
-    <>
-      <FilterOperators column={column} dispatch={dispatch}/>
-      <input
-        type='date'
-        value={value || ''}
-        onChange={(event) => {
-          const targetValue = event.currentTarget.value;
-          const filterRowValue = targetValue ? new Date(targetValue) : null;
-          dispatch(updateFilterRowValue(column.key, filterRowValue));
-        }}
-      />
-    </>
-  );
-};
\ No newline at end of file
diff --git a/src/Demos/MenuItems.tsx b/src/Demos/MenuItems.tsx
index 9ed047d8..2033866f 100644
--- a/src/Demos/MenuItems.tsx
+++ b/src/Demos/MenuItems.tsx
@@ -11,8 +11,8 @@ export class MenuItem {
   public isActive?: boolean;
 }
 
-const newItems: string[] = ['ColumnSettingsDemo'];
-const updateItems: string[] = ['Columns'];
+const newItems: string[] = ['ManyRowsMemoDemo'];
+const updateItems: string[] = ['VirtualScrolling'];
 
 const MenuItems: React.FC<{ items: MenuItem[] }> = ({ items }) => {
 
diff --git a/src/lib/Components/DataRow/DataRow.tsx b/src/lib/Components/DataRow/DataRow.tsx
index d99132e5..f9e2c13c 100644
--- a/src/lib/Components/DataRow/DataRow.tsx
+++ b/src/lib/Components/DataRow/DataRow.tsx
@@ -12,7 +12,6 @@ import EmptyCells from '../EmptyCells/EmptyCells';
 const DataRow: React.FunctionComponent<IRowProps> = (props) => {
   const {
     dispatch,
-    columns,
     groupColumnsCount,
     isSelectedRow,
     rowKeyValue,
@@ -33,11 +32,16 @@ const DataRow: React.FunctionComponent<IRowProps> = (props) => {
   }, props, dataRow);
 
   return (
-    <tr {...elementAttributes} ref={trRef} >
-      <EmptyCells count={groupColumnsCount}/>
+    <tr {...elementAttributes} ref={trRef}>
       {content
-        ? <td className={defaultOptions.css.cell} colSpan={columns.length - groupColumnsCount}>{content}</td>
-        : <DataRowContent {...props}/>}
+        ? <>{content}</>
+        : (
+        <>
+          <EmptyCells count={groupColumnsCount}/>
+          <DataRowContent {...props}/>
+        </>
+        )
+      }
     </tr>
   );
 };
diff --git a/src/lib/Models/FilterCondition.ts b/src/lib/Models/FilterCondition.ts
deleted file mode 100644
index e2eb56c1..00000000
--- a/src/lib/Models/FilterCondition.ts
+++ /dev/null
@@ -1,6 +0,0 @@
-/* Filter condition for specific field */
-export class FilterCondition {
-  public field!: string;
-  public operator!: string;
-  public value!: any;
-}
diff --git a/src/lib/Utils/CellResizeUtils.ts b/src/lib/Utils/CellResizeUtils.ts
index 94ddc9aa..08d0d9bf 100644
--- a/src/lib/Utils/CellResizeUtils.ts
+++ b/src/lib/Utils/CellResizeUtils.ts
@@ -1,5 +1,3 @@
-import { isNumber } from 'util';
-
 import { DispatchFunc } from '../types';
 
 export const HeadCellResizeStateAction = 'HeadCellResizeStateAction';
@@ -26,7 +24,7 @@ export const getValidatedWidth = (newWidth: number, minWidth: number) => {
 export const getMinWidth = (style: any): number => {
   let minWidth: number = 20;
   const styleMinWidth = style && style.minWidth;
-  if (styleMinWidth && isNumber(styleMinWidth)){
+  if (styleMinWidth && typeof styleMinWidth === 'number'){
     minWidth = styleMinWidth;
   }
   return minWidth;
diff --git a/src/lib/Utils/DataUtils.ts b/src/lib/Utils/DataUtils.ts
index fea2b447..d31e2b41 100644
--- a/src/lib/Utils/DataUtils.ts
+++ b/src/lib/Utils/DataUtils.ts
@@ -2,7 +2,7 @@ import { Column } from '../Models/Column';
 import { Field } from '../types';
 import { getField, getFieldParts, getLastField, getLastFieldParents } from './ColumnUtils';
 
-export const getParentValue = (rowData: any, fieldParents: Field[], sameObj = false) => {
+export const getParentValue = (rowData: any, fieldParents: Field[]) => {
   const parentValue = fieldParents.reduce((previousValue, currentValue) => {
     const result = (previousValue && previousValue[currentValue]);
     return result !== undefined ? result : undefined;
@@ -47,7 +47,7 @@ export const getValueByField = (rowData: any, field: Field) => {
   return o;
 };
 
-const _replaceValueForField = (rowData: any, field: Field, newValue: any, fieldParents?: Field[]): void => {
+const replaceValueForField = (rowData: any, field: Field, newValue: any, fieldParents?: Field[]): void => {
   let result = {...rowData};
   if (fieldParents && fieldParents.length) {
     const parentValue = getParentValue(result, fieldParents) || {};
@@ -55,7 +55,7 @@ const _replaceValueForField = (rowData: any, field: Field, newValue: any, fieldP
 
     const parentsOfParent = [...fieldParents];
     const parentFieldName = parentsOfParent.pop() as string;
-    result = _replaceValueForField(result, parentFieldName, parentValue, parentsOfParent);
+    result = replaceValueForField(result, parentFieldName, parentValue, parentsOfParent);
   } else {
     result[field] = newValue;
   }
@@ -63,11 +63,8 @@ const _replaceValueForField = (rowData: any, field: Field, newValue: any, fieldP
 };
 
 export const replaceValue = (rowData: any, column: Column, newValue: any) => {
-  return replaceValueForField(rowData, getField(column), newValue);
-};
-
-export const replaceValueForField = (rowData: any, field: Field, newValue: any) => {
-  return _replaceValueForField(rowData, getLastField(field), newValue, getLastFieldParents(field));
+  const field = getField(column);
+  return replaceValueForField(rowData, getLastField(field), newValue, getLastFieldParents(field));
 };
 
 export const reorderData = (data: any[], getKey: (d: any) => any, keyValue: any, targetKeyValue: any) => {
diff --git a/src/lib/Utils/SortUtils.test.ts b/src/lib/Utils/SortUtils.test.ts
index 7baf9121..3e4ea4be 100644
--- a/src/lib/Utils/SortUtils.test.ts
+++ b/src/lib/Utils/SortUtils.test.ts
@@ -6,11 +6,12 @@ import {
 
 const data: any[] = [
   { column: 1, id: 1 },
+  { column: null, id: 6 },
   { column: 3, id: 2 },
   { column: 2, id: 3 },
   { column: 3, id: 4 },
   { column: 3, id: 5 },
-  { column: null, id: 5 },
+  { column: null, id: 7 },
 ];
 
 const columns: Column[] = [
diff --git a/src/lib/Utils/SortUtils.ts b/src/lib/Utils/SortUtils.ts
index 605a1f0b..d0d3ba42 100644
--- a/src/lib/Utils/SortUtils.ts
+++ b/src/lib/Utils/SortUtils.ts
@@ -29,7 +29,7 @@ export const sortData = (columns: Column[], data: any): any[] => {
   return newData;
 };
 
-export const ascendSort = (sortedColumn: Column) => {
+const ascendSort = (sortedColumn: Column) => {
   return (a: any, b: any) => {
     const aValue = getValueByColumn(a, sortedColumn);
     const bValue = getValueByColumn(b, sortedColumn);
@@ -44,7 +44,7 @@ export const ascendSort = (sortedColumn: Column) => {
   };
 };
 
-export const descendSort = (sortedColumn: Column) => {
+const descendSort = (sortedColumn: Column) => {
   return (a: any, b: any) => {
     const aValue = getValueByColumn(a, sortedColumn);
     const bValue = getValueByColumn(b, sortedColumn);
diff --git a/src/lib/Utils/__snapshots__/SortUtils.test.ts.snap b/src/lib/Utils/__snapshots__/SortUtils.test.ts.snap
index 61e0c64d..c75b61d5 100644
--- a/src/lib/Utils/__snapshots__/SortUtils.test.ts.snap
+++ b/src/lib/Utils/__snapshots__/SortUtils.test.ts.snap
@@ -37,7 +37,11 @@ exports[`sortData should be sorted by Ascend 1`] = `
 Array [
   Object {
     "column": null,
-    "id": 5,
+    "id": 6,
+  },
+  Object {
+    "column": null,
+    "id": 7,
   },
   Object {
     "column": 1,
@@ -86,7 +90,11 @@ Array [
   },
   Object {
     "column": null,
-    "id": 5,
+    "id": 6,
+  },
+  Object {
+    "column": null,
+    "id": 7,
   },
 ]
 `;
diff --git a/src/lib/bootstrapCssClasses.ts b/src/lib/bootstrapCssClasses.ts
deleted file mode 100644
index ea23b654..00000000
--- a/src/lib/bootstrapCssClasses.ts
+++ /dev/null
@@ -1,11 +0,0 @@
-import { CssClasses } from './Models/CssClasses';
-
-const bootstrapCssClasses = new CssClasses();
-bootstrapCssClasses.table = 'table table-striped';
-bootstrapCssClasses.thead = 'thead-dark';
-bootstrapCssClasses.checkbox = 'form-control';
-bootstrapCssClasses.dateInput = 'form-control';
-bootstrapCssClasses.numberInput = 'form-control';
-bootstrapCssClasses.textInput = 'form-control';
-
-export default bootstrapCssClasses;
diff --git a/src/lib/models.ts b/src/lib/models.ts
index 9088a365..97868236 100644
--- a/src/lib/models.ts
+++ b/src/lib/models.ts
@@ -4,7 +4,6 @@ export * from './Models/EditableCell';
 export * from './Models/ChildComponents';
 export * from './Models/Column';
 export * from './Models/CssClasses';
-export * from './Models/FilterCondition';
 export * from './Models/Group';
 export * from './Models/GroupRowData';
 export * from './Models/VirtualScrolling';