UI string tweak

src/chrome/locale/en-US/clippings.dtd

@@ -223,7 +223,7 @@
 <!ENTITY defaultValue.description "Separate multiple values with a ''|'' symbol.  Example: red|green|blue">
 <!ENTITY autoIncrement.description "When the clipping is pasted, you will be prompted for the starting numeric value.  The value will automatically increase by one every time the same clipping is pasted, until it is reset from the Clippings context menu.">
 <!ENTITY dateTimePlchldr.title "Insert Date/Time Placeholder">
-<!ENTITY dateTimeFmts.label "Available formats:">
+<!ENTITY dateTimeFmts.label "Available date/time formats:">
 
 <!-- Import dialog -->
 <!ENTITY import.title "Import Clippings">