--- a/toolkit/content/license.html
+++ b/toolkit/content/license.html
@@ -71,16 +71,17 @@
       <li><a href="about:license#agg">Anti-Grain Geometry Public License</a></li>
       <li><a href="about:license#apache">Apache License 2.0</a></li>
       <li><a href="about:license#apple">Apple License</a></li>
       <li><a href="about:license#apple-mozilla">Apple/Mozilla NPRuntime License</a></li>
       <li><a href="about:license#arm">ARM License</a></li>
       <li><a href="about:license#atty">atty License</a></li>
       <li><a href="about:license#babel">Babel License</a></li>
       <li><a href="about:license#babylon">Babylon License</a></li>
+      <li><a href="about:license#base64">base64 License</a></li>
       <li><a href="about:license#bindgen">bindgen License</a></li>
       <li><a href="about:license#bspatch">bspatch License</a></li>
       <li><a href="about:license#cairo">Cairo Component Licenses</a></li>
       <li><a href="about:license#chromium">Chromium License</a></li>
       <li><a href="about:license#codemirror">CodeMirror License</a></li>
       <li><a href="about:license#cubic-bezier">cubic-bezier License</a></li>
       <li><a href="about:license#d3">D3 License</a></li>
       <li><a href="about:license#dagre-d3">Dagre-D3 License</a></li>
@@ -2778,16 +2779,48 @@ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE F
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 </pre>
 
 
     <hr>
 
+    <h1><a id="base64"></a>base64 License</h1>
+
+    <p>This license applies to files in the directory
+    <code>third_party/rust/base64</code>.</p>
+
+<pre>
+The MIT License (MIT)
+
+Copyright (c) 2015 Alice Maz
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+</pre>
+
+
+    <hr>
+
     <h1><a id="bindgen"></a>bindgen License</h1>
 
     <p>This license applies to this file in the directory
     <code>third_party/rust/bindgen</code>.</p>
 
 <pre>
 Copyright (c) 2013, Jyun-Yan You