Go first; element (4)
I believe the answer is:
lead
<span class="explanation-format__ClueExplanation">I believe this clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">go first</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >'<span class="explanation-format__original">element</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I know that lead is a superconducting element)</span><br/ ><br/ ></span>
(Other definitions for lead that I've seen before include "Guide the heavy metal" , "Be ahead of - guide" , "Guide, direct" , "Actor playing the principal role" , "Church windows include this" .)