Optimize comma

jsfuck.js

@@ -90,7 +90,7 @@
     ')':   '(true+[]["filter"])[20]',
     '*':   USE_CHAR_CODE,
     '+':   '(+(+!+[]+(!+[]+[])[!+[]+!+[]+!+[]]+[+!+[]]+[+[]]+[+[]])+[])[2]',
-    ',':   '[[]]["concat"]([[]])+""',
+    ',':   '([]["slice"]["call"](false+"")+"")[1]',
     '-':   '(+(.+[0000000001])+"")[2]',
     '.':   '(+(+!+[]+[+!+[]]+(!![]+[])[!+[]+!+[]+!+[]]+[!+[]+!+[]]+[+[]])+[])[+!+[]]',
     '/':   '(false+[0])["italics"]()[10]',

output.txt

@@ -10,7 +10,7 @@
 `)` 147
 `*` 6408
 `+` 70
-`,` 498
+`,` 469
 `-` 153
 `.` 72
 `/` 304