diff --git a/mail/js/app.js b/mail/js/app.js
index 421cc9f89b..ecf244ff7e 100644
--- a/mail/js/app.js
+++ b/mail/js/app.js
@@ -169,6 +169,7 @@ app.classes.mail = AppJS.extend(
 				this.mail_isMainWindow = true;
 				var previewPane = this.egw.preference('previewPane', 'mail');
 				this.mail_disablePreviewArea(previewPane !== 'fixed' && previewPane !== 'vertical');
+				if (previewPane == 'vertical') nm.header.right_div.addClass('vertical_splitter');
 				//Get initial folder status
 				this.mail_refreshFolderStatus(undefined,undefined,false);
 
diff --git a/mail/templates/default/app.css b/mail/templates/default/app.css
index 3f542488ec..ff1d6a844d 100644
--- a/mail/templates/default/app.css
+++ b/mail/templates/default/app.css
@@ -903,4 +903,7 @@ div.mailComposeHeaderSection>table {
 
 #mail-index_nm.et2_nextmatch .egwGridView_outer thead tr {border-left: 12px solid transparent;}
 
-#mail-compose_mailaccount {max-width: 100% !important;}
\ No newline at end of file
+#mail-compose_mailaccount {max-width: 100% !important;}
+
+.header_row_right.vertical_splitter {float:left;}
+.header_row_right.vertical_splitter div#mail-index_mail-index-vacationnotice .et2_vbox {margin-right: 0;}
\ No newline at end of file
diff --git a/mail/templates/mobile/app.css b/mail/templates/mobile/app.css
index 68d6cf74ca..a71e0085e2 100644
--- a/mail/templates/mobile/app.css
+++ b/mail/templates/mobile/app.css
@@ -890,6 +890,12 @@ div.mailComposeHeaderSection > table {
 #mail-compose_mailaccount {
   max-width: 100% !important;
 }
+.header_row_right.vertical_splitter {
+  float: left;
+}
+.header_row_right.vertical_splitter div#mail-index_mail-index-vacationnotice .et2_vbox {
+  margin-right: 0;
+}
 #popupMainDiv {
   padding: 5px;
 }
diff --git a/mail/templates/pixelegg/app.css b/mail/templates/pixelegg/app.css
index ce78afd587..303800e3e4 100755
--- a/mail/templates/pixelegg/app.css
+++ b/mail/templates/pixelegg/app.css
@@ -878,6 +878,12 @@ div.mailComposeHeaderSection > table {
 #mail-compose_mailaccount {
   max-width: 100% !important;
 }
+.header_row_right.vertical_splitter {
+  float: left;
+}
+.header_row_right.vertical_splitter div#mail-index_mail-index-vacationnotice .et2_vbox {
+  margin-right: 0;
+}
 #popupMainDiv {
   padding: 5px;
 }