'undo', undo the last replacement; bound to 'u'.
'undo-all', undo all replacements; bound to 'U'.
+** 'delete-trailing-whitespace' deletes whitespace after form feed.
+In modes where form feed was treated as a whitespace character,
+'delete-trailing-whitespace' would keep lines containing it unchanged.
+It now deletes whitespace after the last form feed thus behaving the
+same as in modes where the character is not whitespace.
+
\f
* Changes in Specialized Modes and Packages in Emacs 25.2