diff --git a/api/js/jsapi/egw_timer.js b/api/js/jsapi/egw_timer.js
index 731d4c7060..b58ca823b4 100644
--- a/api/js/jsapi/egw_timer.js
+++ b/api/js/jsapi/egw_timer.js
@@ -670,9 +670,13 @@ egw.extend('timer', egw.MODULE_GLOBAL, function()
 								}
 								else
 								{
-									egw.request('EGroupware\\Timesheet\\Events::ajax_dontAskAgainWorkingTime');
+									egw.request('EGroupware\\Timesheet\\Events::ajax_dontAskAgainWorkingTime', button !== Et2Dialog.NO_BUTTON);
 								}
-							}, 'Do you want to start your working time?', 'Working time', {}, Et2Dialog.BUTTONS_YES_NO);
+							}, 'Do you want to start your working time?', 'Working time', {}, 		[
+								{button_id: Et2Dialog.YES_BUTTON, label: egw.lang('yes'), id: 'dialog[yes]', image: 'check', "default": true},
+								{button_id: Et2Dialog.NO_BUTTON, label: egw.lang('no'), id: 'dialog[no]', image: 'cancel'},
+								{button_id: "dont_ask_again", label: egw.lang("Don't ask again!"), id: 'dialog[dont_ask_again]', image:'save', align: "right"}
+							]);
 						}
 						// overall timer running for more than 16 hours, ask to stop
 						else if (overall?.start && (((new Date()).valueOf() - overall.start.valueOf()) / 3600000) >= 16)
diff --git a/api/lang/egw_de.lang b/api/lang/egw_de.lang
index e4f038c8c6..ff2b3e5e1e 100644
--- a/api/lang/egw_de.lang
+++ b/api/lang/egw_de.lang
@@ -453,6 +453,7 @@ domain name for mail-address, eg. "%1"	common	de	Domainname für E-Mail Adresse,
 domestic	common	de	Inland
 dominica	common	de	DOMINICA
 dominican republic	common	de	DOMINIKANISCHE REPUBLIK
+don't ask again!	common	de	Nicht wieder fragen!
 don't show this again	common	de	Text nicht mehr anzeigen
 done	common	de	erledigt
 dos international	common	de	DOS International
diff --git a/api/lang/egw_en.lang b/api/lang/egw_en.lang
index 0849772021..a7fdf0556c 100644
--- a/api/lang/egw_en.lang
+++ b/api/lang/egw_en.lang
@@ -453,6 +453,7 @@ domain name for mail-address, eg. "%1"	common	en	Domain name for mail address, e
 domestic	common	en	Domestic
 dominica	common	en	DOMINICA
 dominican republic	common	en	DOMINICAN REPUBLIC
+don't ask again!	common	en	Don't ask again!
 don't show this again	common	en	Don't show this again
 done	common	en	Done
 dos international	common	en	DOS International
diff --git a/timesheet/src/Events.php b/timesheet/src/Events.php
index 78fe889f91..a5ff8bee19 100644
--- a/timesheet/src/Events.php
+++ b/timesheet/src/Events.php
@@ -318,13 +318,24 @@ class Events extends Api\Storage\Base
 	}
 
 	/**
-	 * Remember for 18h to not ask again to start working time
+	 * Remember for 18h or forever to not ask again to start working time
 	 *
+	 * @param ?bool $never true: never ask again, set preference, otherwise remember in session for 18h
 	 * @return void
 	 */
-	static function ajax_dontAskAgainWorkingTime()
+	static function ajax_dontAskAgainWorkingTime(bool $never=null)
 	{
-		Api\Cache::setSession(__CLASS__, self::DONT_ASK_AGAIN_WORKING_TIME, true, 18*3600);
+		if ($never)
+		{
+			$prefs = new Api\Preferences($GLOBALS['egw_info']['user']['account_id']);
+			$prefs->read_repository();
+			$prefs->user['timesheet']['workingtime_session'] = 'no';
+			$prefs->save_repository();
+		}
+		else
+		{
+			Api\Cache::setSession(__CLASS__, self::DONT_ASK_AGAIN_WORKING_TIME, true, 18*3600);
+		}
 	}
 
 	/**