=QUERY(TRANSPOSE(QUERY(TRANSPOSE(F1:I), 
 "select "&REGEXREPLACE(JOIN( , ARRAYFORMULA(IF(LEN(F1:F&G1:G&H1:H&I1:I), 
 "max(Col"&ROW(F1:F)-ROW(F1)+1&"),", ""))), ".\z", "")&"")),
 "select Col2")