Lost brightness (5)
I believe the answer is:
faded
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">lost brightness</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 faded that I've seen before include "Washed-out, dimmed" , "Bleached or deteriorated" , "went off line" , "Washed out" , "Lost youth" .)