Fix remaining issues from mimetype icon rename

diff --git a/konqueror/sidebar/sidebar_widget.cpp b/konqueror/sidebar/sidebar_widget.cpp
index 096cd08..8eefa7c 100644
--- a/konqueror/sidebar/sidebar_widget.cpp
+++ b/konqueror/sidebar/sidebar_widget.cpp
@@ -874,7 +874,7 @@
 					if (!m_buttonPopup)
 					{
 						m_buttonPopup=new TDEPopupMenu(this, "Sidebar_Widget::ButtonPopup");
-						m_buttonPopup->insertTitle(SmallIcon("text-x-katefilelist"), "", 50);
+						m_buttonPopup->insertTitle(SmallIcon("unknown"), "", 50);
 						m_buttonPopup->insertItem(SmallIconSet("text"), i18n("Set Name..."),4); // Item to open a dialog to change the name of the sidebar item (by Pupeno)
 						m_buttonPopup->insertItem(SmallIconSet("www"), i18n("Set URL..."),2);
 						m_buttonPopup->insertItem(SmallIconSet("icons"), i18n("Set Icon..."),1);