diff --git a/lisp/tab-line.el b/lisp/tab-line.el
index 61a0201b298..8da554a3267 100644
--- a/lisp/tab-line.el
+++ b/lisp/tab-line.el
@@ -647,7 +647,7 @@ using the `previous-buffer' command."
 If non-nil, `tab-line-switch-to-prev-tab' in the first tab
 switches to the last tab and `tab-line-switch-to-next-tab' in the
 last tab switches to the first tab.  This variable is not consulted
-when `tab-line-tabs-function' is `tab-line-tabs-window-buffers'"
+when `tab-line-tabs-function' is `tab-line-tabs-window-buffers'."
   :type 'boolean
   :group 'tab-line
   :version "28.1")