diff --git a/src/panel/widgets/notifications/single-notification.cpp b/src/panel/widgets/notifications/single-notification.cpp
index 034a1e16..0fe4ef71 100644
--- a/src/panel/widgets/notifications/single-notification.cpp
+++ b/src/panel/widgets/notifications/single-notification.cpp
@@ -2,6 +2,7 @@
 #include "daemon.hpp"
 
 #include <glibmm/main.h>
+#include <glibmm/markup.h>
 #include <gtk-utils.hpp>
 #include <gtkmm/icontheme.h>
 
@@ -111,11 +112,12 @@ WfSingleNotification::WfSingleNotification(const Notification & notification)
     text.set_line_wrap_mode(Pango::WRAP_CHAR);
     if (notification.body.empty())
     {
-        text.set_markup(notification.summary);
+        text.set_markup(Glib::Markup::escape_text(notification.summary));
     } else
     {
         // NOTE: that is not a really right way to implement FDN markup feature, but the easiest one.
-        text.set_markup("<b>" + notification.summary + "</b>" + "\n" + notification.body);
+        text.set_markup("<b>" + Glib::Markup::escape_text(
+            notification.summary) + "</b>" + "\n" + Glib::Markup::escape_text(notification.body));
     }
 
     content.pack_start(text);
diff --git a/src/panel/widgets/tray/item.cpp b/src/panel/widgets/tray/item.cpp
index 98c5a1d3..dfc0c84f 100644
--- a/src/panel/widgets/tray/item.cpp
+++ b/src/panel/widgets/tray/item.cpp
@@ -2,6 +2,8 @@
 
 #include <gtk-utils.hpp>
 
+#include <glibmm/markup.h>
+
 #include <gtkmm/icontheme.h>
 #include <gtkmm/tooltip.h>
 
@@ -185,10 +187,11 @@ void StatusNotifierItem::setup_tooltip()
             get_item_property<std::tuple<Glib::ustring, IconData, Glib::ustring, Glib::ustring>>("ToolTip");
 
         auto tooltip_label_text = !tooltip_text.empty() && !tooltip_title.empty() ?
-            "<b>" + tooltip_title + "</b>: " + tooltip_text :
-            !tooltip_title.empty() ? tooltip_title :
-            !tooltip_text.empty() ? tooltip_text :
-            get_item_property<Glib::ustring>("Title");
+            "<b>" + Glib::Markup::escape_text(tooltip_title) + "</b>: " +
+            Glib::Markup::escape_text(tooltip_text) :
+            !tooltip_title.empty() ? Glib::Markup::escape_text(tooltip_title) :
+            !tooltip_text.empty() ? Glib::Markup::escape_text(tooltip_text) :
+            Glib::Markup::escape_text(get_item_property<Glib::ustring>("Title"));
 
         const auto pixbuf = extract_pixbuf(std::move(tooltip_icon_data));