diff --git a/admin/inc/class.admin_ui.inc.php b/admin/inc/class.admin_ui.inc.php
index ef1f147912..102c425ee2 100644
--- a/admin/inc/class.admin_ui.inc.php
+++ b/admin/inc/class.admin_ui.inc.php
@@ -275,11 +275,19 @@ class admin_ui
 
 		$group = 5;	// allow to place actions in different groups by hook, this is the default
 
-		// supporting both old way using $GLOBALS['menuData'] and new just returning data in hook
-		$apps = array_unique(array_merge(array('admin'), Api\Hooks::implemented('edit_group')));
+		$apps = Api\Hooks::implemented('edit_group');
+		// register hooks, if no admin one, can be removed after 22.1
+		if (!isset($apps['admin']))
+		{
+			Api\Hooks::read(true);
+			$apps = Api\Hooks::implemented('edit_group');
+		}
+		// skip EPL and groups app, in case their group-admin is still installed
+		$apps = array_unique(array_diff($apps, ['groups', 'stylite']));
 		foreach($apps as $app)
 		{
-			$GLOBALS['menuData'] = $data = array();
+			// supporting both old way using $GLOBALS['menuData'] and new just returning data in hook
+			$GLOBALS['menuData'] = [];
 			$data = Api\Hooks::single('edit_group', $app);
 			if (!is_array($data)) $data = $GLOBALS['menuData'];
 
@@ -678,4 +686,4 @@ class admin_ui
 		self::$accounts = $GLOBALS['egw']->accounts;
 	}
 }
-admin_ui::init_static();
+admin_ui::init_static();
\ No newline at end of file
diff --git a/admin/js/app.ts b/admin/js/app.ts
index c78de0d372..c46831da81 100644
--- a/admin/js/app.ts
+++ b/admin/js/app.ts
@@ -1513,6 +1513,84 @@ class AdminApp extends EgwApp
 			cmds_preview.set_value({content:[data.data]});
 		}
 	}
+
+	/*******************************************************************************************************************
+	 * Groupadmin methods
+	 ******************************************************************************************************************/
+
+	/**
+	 * ACL button clicked
+	 *
+	 * @param {jQuery.Event} _ev
+	 * @param {et2_button} _widget
+	 */
+	aclGroup(_ev, _widget)
+	{
+		let app = _widget.id.substr(7, _widget.id.length-8);	// button[appname]
+		let apps = this.et2.getArrayMgr('content').getEntry('apps');
+		for (let i=0; i < apps.length; i++)
+		{
+			let data = apps[i];
+			if (data.appname == app && data.action)
+			{
+				if (data.action === true)
+				{
+					data.action = this.egw.link('/index.php', {
+						menuaction: 'admin.admin_acl.index',
+						account_id: this.et2.getArrayMgr('content').getEntry('account_id'),
+						acl_filter: 'other',
+						acl_app: app
+					});
+					data.popup = '900x450';
+				}
+				egw(opener).open_link(data.action, data.popup ? '_blank' : '_self', data.popup);
+				break;
+			}
+		}
+	}
+
+	/**
+	 * Delete button clicked
+	 *
+	 * @param {jQuery.Event} _ev
+	 * @param {et2_button} _widget
+	 */
+	deleteGroup(_ev, _widget)
+	{
+		let account_id = this.et2.getArrayMgr('content').getEntry('account_id');
+		let egw = this.egw;
+
+		Et2Dialog.show_dialog(function(button)
+		{
+			if(button == Et2Dialog.YES_BUTTON)
+			{
+				egw.json('admin_account::ajax_delete_group', [account_id]).sendRequest(false);	// false = synchronious request
+				window.close();
+			}
+		}, this.egw.lang('Delete this group') + '?');
+	}
+
+	/**
+	 * Field changed, call server validation
+	 *
+	 * @param {jQuery.Event} _ev
+	 * @param {et2_button} _widget
+	 */
+	changeGroup(_ev, _widget)
+	{
+		let account_id = this.et2.getArrayMgr('content').getEntry('account_id');
+		let data = {account_id: account_id};
+		data[_widget.id] = _widget.getValue();
+
+		this.egw.json('EGroupware\\Admin\\Groups::ajax_check', [data], function(_msg)
+		{
+			if (_msg)
+			{
+				egw(window).message(_msg, 'error');	// context gets lost :(
+				_widget.getDOMNode().focus();
+			}
+		}, this).sendRequest();
+	}
 }
 
 app.classes.admin = AdminApp;
\ No newline at end of file
diff --git a/admin/setup/setup.inc.php b/admin/setup/setup.inc.php
index f2fe587256..8cd47ebcf6 100644
--- a/admin/setup/setup.inc.php
+++ b/admin/setup/setup.inc.php
@@ -33,6 +33,7 @@ $setup_info['admin']['hooks']['admin'] = 'admin_hooks::all_hooks';
 $setup_info['admin']['hooks']['sidebox_menu'] = 'admin_hooks::all_hooks';
 $setup_info['admin']['hooks']['edit_user'] = 'admin_hooks::edit_user';
 $setup_info['admin']['hooks']['config'] = 'admin_hooks::config';
+$setup_info['admin']['hooks']['edit_group'] = \EGroupware\Admin\Groups::class.'::edit_group';
 
 // add account tab to addressbook.edit
 $setup_info['admin']['hooks']['addressbook_edit'] = 'admin.admin_account.addressbook_edit';
@@ -41,4 +42,4 @@ $setup_info['admin']['hooks']['addressbook_edit'] = 'admin.admin_account.address
 $setup_info['admin']['depends'][] = array(
 	'appname' => 'api',
 	'versions' => Array('21.1')
-);
+);
\ No newline at end of file
diff --git a/admin/src/Groups.php b/admin/src/Groups.php
new file mode 100644
index 0000000000..abd36bf766
--- /dev/null
+++ b/admin/src/Groups.php
@@ -0,0 +1,405 @@
+<?php
+/**
+ * EGroupware: Group administration
+ *
+ * @link https://www.egroupware.org
+ * @package admin
+ * @author Ralf Becker <rb@egroupware.org>
+ * @copyright (c) 2014-22 by Ralf Becker <rb@egroupware.org>
+ */
+
+namespace EGroupware\Admin;
+
+use EGroupware\Api;
+use EGroupware\Api\Framework;
+use EGroupware\Api\Egw;
+use EGroupware\Api\Acl;
+use EGroupware\Api\Etemplate;
+
+/**
+ * Group administration:
+ * - hooks into admin to add and edit groups
+ */
+class Groups
+{
+	/**
+	 * Methods callable via menuaction
+	 *
+	 * @var array
+	 */
+	var $public_functions = array(
+		'edit' => true,
+	);
+
+	/**
+	 * Reference to global accounts object
+	 *
+	 * @var Api\Accounts
+	 */
+	protected $accounts;
+	/**
+	 * Reference to global acl class (instantiated for current user)
+	 *
+	 * @var Acl
+	 */
+	protected $acl;
+
+	/**
+	 * Apps supporting (group) ACL
+	 *
+	 * @var type
+	 */
+	protected $apps_with_acl = array(
+		'calendar'    => True,
+		'infolog'     => True,
+		'filemanager' => array(
+			'menuaction' => 'filemanager.filemanager_ui.file',
+			'path' => '/home/$account_lid',
+			'tabs' => 'eacl',
+			'popup' => '495x400',
+		),
+		'bookmarks'   => True,
+		'phpbrain'    => True,
+		'projectmanager' => True,
+		'timesheet'   => True
+	);
+
+	/**
+	 * Constructor
+	 */
+	public function __construct()
+	{
+		$this->acl = $GLOBALS['egw']->acl;
+		$this->accounts = $GLOBALS['egw']->accounts;
+
+		foreach(Api\Hooks::process('group_acl','',true) as $app => $data)
+		{
+			if ($data) $this->apps_with_acl[$app] = $data;
+		}
+		// we need admin translations
+		Api\Translation::add_app('admin');
+	}
+
+	/**
+	 * Edit / add a group
+	 *
+	 * @param array $content =null
+	 */
+	public function edit(array $content=null)
+	{
+		$sel_options = $readonlys = array();
+		$tpl = new Etemplate('admin.group.edit');
+
+		if (!is_array($content))
+		{
+			if (isset($_GET['account_id']))
+			{
+				// invalidate account, before reading it, to code with changed to DB or LDAP outside EGw
+				Api\Accounts::cache_invalidate((int)$_GET['account_id']);
+				if ($this->accounts->exists((int)$_GET['account_id']) != 2 ||	// 2 = group
+					!($content = $this->accounts->read((int)$_GET['account_id'])))
+				{
+					Framework::window_close(lang('Entry not found!'));
+				}
+				if ($GLOBALS['egw']->acl->check('group_access', 8, 'admin'))	// no view
+				{
+					Framework::window_close(lang('Permission denied!'));
+				}
+				$content['account_members'] = array_keys($content['members']);
+				unset($content['members']);
+				// we might not see all (system) users, so preserve them
+				foreach($content['account_members'] as $key => $id)
+				{
+					if ($id < 0 || !$this->accounts->id2name($id))
+					{
+						$content['unaccessible_members'][] = $id;
+						unset($content['account_members'][$key]);
+					}
+				}
+				$content['old'] = $content;
+			}
+			else
+			{
+				if ($GLOBALS['egw']->acl->check('group_access', 4, 'admin'))	// no add
+				{
+					Framework::window_close(lang('Permission denied!'));
+				}
+				$content = array();
+			}
+			//call_user_func(base64_decode('c3R5bGl0ZV9saWNlbnNlX2JvOjp2YWxpZGF0ZQ=='));
+		}
+		elseif(!empty($content['button']))
+		{
+			$button = key($content['button']);
+			unset($content['button']);
+			$msg = '';
+
+			switch($button)
+			{
+				case 'apply':
+				case 'save':
+					try {
+						$refresh_type = !$content['old'] ? 'add' : 'edit';
+						// check if some account-data changed
+						if (!$content['old'] || $content['old'] != array_intersect_key($content, $content['old']))
+						{
+							if (!empty($content['unaccessible_members']))
+							{
+								$content['account_members'] = array_merge($content['account_members'], $content['unaccessible_members']);
+							}
+
+							// Only set real changes
+							$content['account_id'] = $this->run_command($content, $msg);
+
+							if (!empty($content['unaccessible_members']))
+							{
+								$content['account_members'] = array_diff($content['account_members'], $content['unaccessible_members']);
+							}
+							$content['old'] = array_intersect_key($content, $content['old'] ? $content['old'] :
+								array_flip(array('account_id','account_lid','account_email','account_members')));
+						}
+						$apps = array();
+						foreach((array)$content['apps'] as $data)
+						{
+							if ($data['run']) $apps[] = $data['appname'];
+						}
+						//error_log(__METHOD__."() apps=".array2string($apps).", old=".array2string($content['old_run']).", content[apps]=".array2string($content['apps']));
+						// check if new apps added
+						if (($added = array_diff($apps, $content['old_run'])))
+						{
+							//error_log(__METHOD__."() apps added: ".array2string($added));
+							$allow = array(
+								'allow' => true,
+								'account' => $content['account_id'],
+								'apps' => $added,
+							// This is the documentation from policy app
+							)+(array)$content['admin_cmd'];
+							$add_cmd = new admin_cmd_account_app($allow);
+							$msg .= $add_cmd->run();
+						}
+						// check if apps being removed
+						if (($removed = array_diff($content['old_run'], $apps)))
+						{
+							//error_log(__METHOD__."() apps removed: ".array2string($removed));
+							$allow = array(
+								'allow' => false,
+								'account' => $content['account_id'],
+								'apps' => $removed,
+							// This is the documentation from policy app
+							)+(array)$content['admin_cmd'];
+							$rm_cmd = new admin_cmd_account_app($allow);
+							$msg .= $rm_cmd->run();
+						}
+						$content['old_run'] = $apps;
+					}
+					catch (Exception $ex) {
+						$msg .= $ex->getMessage();
+						unset($button);	// do NOT close dialog
+					}
+					if (!$msg)
+					{
+						$msg = lang('Nothing to save.');
+					}
+					else
+					{
+						Framework::refresh_opener($msg, 'admin', $content['account_id'], $refresh_type, null, null, null,
+							isset($ex) ? 'error' : 'success');
+					}
+					if ($button != 'save')
+					{
+						Framework::message($msg, isset($ex) ? 'error' : 'success');
+						break;
+					}
+					Framework::window_close();
+			}
+		}
+		$run_rights = $content['account_id'] ? $this->acl->get_user_applications($content['account_id'], false, false) : array();
+		$content['apps'] = $content['old_run'] = array();
+		foreach($GLOBALS['egw_info']['apps'] as $app => $data)
+		{
+			if (!$data['enabled'] || !$data['status'] || $data['status'] == 3)
+			{
+				continue;	// do NOT show disabled apps, or our API (status = 3)
+			}
+
+			$popup = null;
+			$acl_action = $this->_acl_action($app, $content['account_id'], $content['account_lid'], $popup);
+
+			$content['apps'][] = array(
+				'appname' => $app,
+				'title' => lang($app),
+				'action' => $acl_action,
+				'popup' => $popup,
+				'run' => (int)(boolean)$run_rights[$app],
+			);
+			if ($run_rights[$app]) $content['old_run'][] = $app;
+			$readonlys['apps']['button['.$app.']'] = !$acl_action;
+		}
+		usort($content['apps'], function($a, $b)
+		{
+			if ($a['run'] !== $b['run']) return $b['run']-$a['run'];
+			return strcasecmp($a['title'], $b['title']);
+		});
+
+		$readonlys['button[delete]'] = !$content['account_id'] ||
+			$GLOBALS['egw']->acl->check('group_access', 32, 'admin');	// no delete
+		if ($GLOBALS['egw']->acl->check('group_access', $content['account_id'] ? 16 : 4, 'admin'))	// no edit / add
+		{
+			$readonlys['button[save]'] = $readonlys['button[apply]'] = true;
+		}
+
+		$tpl->exec('admin.'.self::class.'.edit', $content, $sel_options, $readonlys, $content, 2);
+	}
+
+	/**
+	 * Run the admin command to save the account change & log it
+	 *
+	 * @param Array $content Content from etemplate save
+	 *
+	 * @return int Command account
+	 */
+	public function run_command($content, &$msg)
+	{
+		$fields = array(
+			'account_email',
+			'account_lid',
+			'account_description',
+			'account_members',
+		);
+		// Only send real changes
+		$account = array();
+		$old = array_intersect_key((array)$content['old'], array_flip($fields));
+		foreach($fields as $field)
+		{
+			if($old && $content[$field] == $old[$field])
+			{
+				unset($old[$field]);
+				continue;
+			}
+			switch($field)
+			{
+				case 'account_members':
+					sort($content[$field]);
+					if (is_array($old[$field])) sort($old[$field]);
+					if($content[$field] == $old[$field])
+					{
+						unset($old[$field]);
+						continue 2;
+					}
+				default:
+					$account[$field] = $content[$field];
+			}
+		}
+
+		// No changes here
+		if(count($account) == 0) return $content['account_id'];
+
+		$cmd = new admin_cmd_edit_group(array(
+			'account' => (int)$content['account_id'],
+			'set' => $account,
+			'old' => $old,
+		// This is the documentation from policy app
+		)+(array)$content['admin_cmd']);
+		$msg = $cmd->run();
+		return $cmd->account;
+	}
+	/**
+	 * Check entered data and return error-msg via json data or null
+	 *
+	 * @param array $data values for account_id and account_lid
+	 */
+	public static function ajax_check(array $data)
+	{
+		// set dummy member to get no error about no members yet
+		$data['account_members'] = array($GLOBALS['egw_info']['user']['account_id']);
+
+		try {
+			$cmd = new admin_cmd_edit_group($data['account_id'], $data);
+			$cmd->run(null, false, false, true);
+		}
+		catch(Exception $e)
+		{
+			Api\Json\Response::get()->data($e->getMessage());
+		}
+	}
+
+	/**
+	 * Return actions for groups / edit_group hook
+	 *
+	 * @param string|array $location
+	 */
+	public static function edit_group($location)
+	{
+		unset($location);	// unused, but required by hooks signature
+
+		$ret = array(
+			array(
+				'id' => 'edit',
+				'caption' => 'Edit group',
+				'icon' => 'edit',
+				'popup' => '600x400',
+				'url' => 'menuaction=admin.'.self::class.'.edit&account_id=$id',
+				'group' => 2,
+			),
+			array(
+				'id' => 'add_group',
+				'caption' => 'Add group',
+				'icon' => 'new',
+				'popup' => '600x400',
+				'url' => 'menuaction=admin.'.self::class.'.edit',
+				'group' => 2,
+				'enableId' => '',
+			),
+			'delete' => array(
+				'id' => 'delete',
+				'caption' => 'Delete',
+				'icon' => 'delete',
+				'confirm' => 'Delete this group',
+				'group' => 99,
+			)
+		);
+		// if policy app is used, use admin_account delete to delete groups
+		if ($GLOBALS['egw_info']['user']['apps']['policy'])
+		{
+			$ret['delete'] += array(
+				'policy_confirmation' => true,
+				'url' => 'menuaction=admin.admin_account.delete&account_id=$id'
+			);
+		}
+		return $ret;
+	}
+
+	/**
+	 * Check if app uses group ACL
+	 *
+	 * @param string $app
+	 * @param int $account_id
+	 * @param string $account_lid
+	 * @param string &$popup on return $width.'x'.$height or null
+	 * @return boolean|string false or link for action
+	 */
+	private function _acl_action($app, $account_id, $account_lid, &$popup)
+	{
+		if (!($acl_action = $this->apps_with_acl[$app]) || !$account_id)
+		{
+			return false;
+		}
+		if ($acl_action === true)
+		{
+			return true;
+		}
+		$replacements = array(
+			'$app' => $app,
+			'$account_id' => $account_id,
+			'$account_lid' => $account_lid,
+		);
+		foreach($acl_action as &$value)
+		{
+			$value = str_replace(array_keys($replacements), array_values($replacements), $value);
+		}
+		$popup = $acl_action['popup'];
+		unset($acl_action['popup']);
+
+		return Egw::link('/index.php',$acl_action);
+	}
+}
\ No newline at end of file
diff --git a/admin/templates/default/group.edit.xet b/admin/templates/default/group.edit.xet
new file mode 100644
index 0000000000..9c8db5294c
--- /dev/null
+++ b/admin/templates/default/group.edit.xet
@@ -0,0 +1,62 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE overlay PUBLIC "-//EGroupware GmbH//eTemplate 2//EN" "http://www.egroupware.org/etemplate2.dtd">
+<!-- $Id$ -->
+<overlay>
+	<template id="admin.group.edit.members" template="" lang="" group="0" version="1.9.001">
+		<select-account account_type="accounts" id="account_members" multiple="true" class="et2_fullWidth" needed="true" tags="true"/>
+	</template>
+	<template id="admin.group.edit.apps" template="" lang="" group="0" version="1.9.001">
+		<grid width="100%" id="apps" overflow="auto" height="200" resize_ratio="1">
+			<columns>
+				<column/>
+				<column/>
+				<column/>
+			</columns>
+			<rows>
+				<row>
+					<appicon align="center" src="$row_cont[appname]"/>
+					<checkbox label="$row_cont[appname]" id="${row}[run]"/>
+					<button label="ACL" id="button[$row_cont[appname]]" image="edit" title="Edit ACL" onclick="app.admin.aclGroup"/>
+				</row>
+			</rows>
+		</grid>
+	</template>
+	<template id="admin.group.edit" template="" lang="" group="0" version="1.9.001">
+		<grid width="100%">
+			<columns>
+				<column width="100px"/>
+				<column/>
+			</columns>
+			<rows>
+				<row class="dialogHeader">
+					<description value="Group name" for="account_lid"/>
+					<textbox id="account_lid" size="40" maxlength="64" class="et2_fullWidth" needed="true" onchange="app.admin.changeGroup"/>
+				</row>
+				<row>
+					<description value="Description" for="account_description"/>
+					<textbox id="account_description" size="40" maxlength="64" class="et2_fullWidth"/>
+				</row>
+				<row disabled="!@mailAllowed">
+					<description value="EMail"/>
+					<url-email id="account_email" size="40" maxlength="64" class="et2_fullWidth"/>
+				</row>
+			</rows>
+		</grid>
+		<tabbox id="tabs" class="et2_nowrap" span="all" width="100%" tab_height="250px">
+			<tabs>
+				<tab id="members" label="Members" statustext="Users in this group"/>
+				<tab id="apps" label="Applications" statustext="Applications this group can use"/>
+			</tabs>
+			<tabpanels>
+				<template id="admin.group.edit.members"/>
+				<template id="admin.group.edit.apps"/>
+			</tabpanels>
+		</tabbox>
+		<hbox class="dialogFooterToolbar">
+			<button label="Save" id="button[save]"/>
+			<button label="Apply" id="button[apply]"/>
+			<button label="Cancel" id="button[cancel]" onclick="window.close();"/>
+			<button align="right" label="Delete" id="button[delete]" onclick="app.admin.deleteGroup"/>
+		</hbox>
+	</template>
+</overlay>
\ No newline at end of file