diff --git a/lisp/ein-notification.el b/lisp/ein-notification.el
index 26f0885..8ae6f11 100644
--- a/lisp/ein-notification.el
+++ b/lisp/ein-notification.el
@@ -40,6 +40,7 @@
 
 (defvar ein:header-line-format '(:eval (ein:header-line)))
 (defvar ein:header-line-tab-map (make-sparse-keymap))
+(defvar ein:header-line-insert-tab-map (make-sparse-keymap))
 (defvar ein:header-line-tab-help
   "\
 mouse-1 (left click) : switch to this tab
@@ -222,26 +223,33 @@ insert-prev insert-next move-prev move-next)"
         (get-name (oref tab :get-name)))
     (ein:join-str
      " "
-     (loop for i from 1
-           for elem in list
-           if (eq elem current)
-           collect (propertize
-                    (or (ein:and-let* ((name (funcall get-name elem)))
-                          (format "/%d: %s\\" i name))
-                        (format "/%d\\" i))
-                    'ein:worksheet elem
-                    'keymap ein:header-line-tab-map
-                    'help-echo ein:header-line-tab-help
-                    'mouse-face 'highlight
-                    'face 'ein:notification-tab-selected)
-           else
-           collect (propertize
-                    (format "/%d\\" i)
-                    'ein:worksheet elem
-                    'keymap ein:header-line-tab-map
-                    'help-echo ein:header-line-tab-help
-                    'mouse-face 'highlight
-                    'face 'ein:notification-tab-normal)))))
+     (append
+      (loop for i from 1
+            for elem in list
+            if (eq elem current)
+            collect (propertize
+                     (or (ein:and-let* ((name (funcall get-name elem)))
+                           (format "/%d: %s\\" i name))
+                         (format "/%d\\" i))
+                     'ein:worksheet elem
+                     'keymap ein:header-line-tab-map
+                     'help-echo ein:header-line-tab-help
+                     'mouse-face 'highlight
+                     'face 'ein:notification-tab-selected)
+            else
+            collect (propertize
+                     (format "/%d\\" i)
+                     'ein:worksheet elem
+                     'keymap ein:header-line-tab-map
+                     'help-echo ein:header-line-tab-help
+                     'mouse-face 'highlight
+                     'face 'ein:notification-tab-normal))
+      (list
+       (propertize "[+]"
+                   'keymap ein:header-line-insert-tab-map
+                   'help-echo "Click (mouse-1) to insert a new tab."
+                   'mouse-face 'highlight
+                   'face 'ein:notification-tab-normal))))))
 
 
 ;;; Header line
@@ -255,6 +263,9 @@ insert-prev insert-next move-prev move-next)"
   (define-key map [header-line mouse-2] 'ein:header-line-delete-this-tab)
   (define-key map [header-line mouse-3] 'ein:header-line-pop-to-this-tab))
 
+(define-key ein:header-line-insert-tab-map
+  [header-line mouse-1] 'ein:header-line-insert-new-tab)
+
 (defmacro ein:with-destructuring-bind-key-event (key-event &rest body)
   (declare (debug (form &rest form))
            (indent 1))
@@ -312,6 +323,14 @@ Generated by `ein:header-line-define-mouse-commands'" slot)
  ein:header-line-move-next-tab :move-next
  )
 
+(defun ein:header-line-insert-new-tab (key-event)
+  "Insert new tab."
+  (interactive "e")
+  (ein:header-line-select-window key-event)
+  (let ((notification (oref ein:%notification% :tab)))
+    (funcall (oref notification :insert-next)
+             (car (last (funcall (oref notification :get-list)))))))
+
 (defun ein:header-line ()
   (format
    "IP[%s]: %s"