"Parsifal" composer (6)
I believe the answer is:
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">parsifal composer</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for wagner that I've seen before include "Richard . . . . . . composer of 'The Flying Dutchman' and 'Lohengrin'" , "Composer of ''The Flying Dutchman'' etc" , "German composer of The Ring Cycle" , "Tannhauser composer" , "Noted German" .)