diff --git a/unpacked/jax/input/TeX/config.js b/unpacked/jax/input/TeX/config.js
index 7329e0430..522d7cff5 100644
--- a/unpacked/jax/input/TeX/config.js
+++ b/unpacked/jax/input/TeX/config.js
@@ -24,7 +24,7 @@
 
 MathJax.InputJax.TeX = MathJax.InputJax({
   id: "TeX",
-  version: "2.1.2",
+  version: "2.1.3",
   directory: MathJax.InputJax.directory + "/TeX",
   extensionDir: MathJax.InputJax.extensionDir + "/TeX",
   
diff --git a/unpacked/jax/input/TeX/jax.js b/unpacked/jax/input/TeX/jax.js
index a51889368..9b966207f 100644
--- a/unpacked/jax/input/TeX/jax.js
+++ b/unpacked/jax/input/TeX/jax.js
@@ -421,7 +421,8 @@
       
       remap: {
         '-':   '2212',
-        '*':   '2217'
+        '*':   '2217',
+        '`':   '2018',  // map ` to back quote
       },
     
       mathchar0mi: {