Help links work on Firefox.

IPython/frontend/html/notebook/static/css/notebook.css

@@ -67,7 +67,11 div.section_content {
     padding: 5px;
 }
 
-span.section_row_buttons > button {
+span.section_row_buttons button {
+    width: 70px;
+}
+
+span.section_row_buttons a {
     width: 70px;
 }
 

IPython/frontend/html/notebook/templates/notebook.html

@@ -157,17 +157,17
             <div class="section_content">
                 <div class="section_row">
                     <span id="help_buttons0" class="section_row_buttons">
-                        <button id="python_help"><a href="http://docs.python.org" target="_blank">Python</a></button>
-                        <button id="ipython_help"><a href="http://ipython.org/documentation.html" target="_blank">IPython</a></button>
-                        <button id="numpy_help"><a href="http://docs.scipy.org/doc/numpy/reference/" target="_blank">NumPy</a></button>
+                        <a id="python_help" href="http://docs.python.org" target="_blank">Python</a>
+                        <a id="ipython_help" href="http://ipython.org/documentation.html" target="_blank">IPython</a>
+                        <a id="numpy_help" href="http://docs.scipy.org/doc/numpy/reference/" target="_blank">NumPy</a>
                     </span>
                     <span class="section_row_header">Links</span>
                 </div>
                 <div class="section_row">
                     <span id="help_buttons1" class="section_row_buttons">
-                        <button id="matplotlib_help"><a href="http://matplotlib.sourceforge.net/" target="_blank">MPL</a></button>
-                        <button id="scipy_help"><a href="http://docs.scipy.org/doc/scipy/reference/" target="_blank">SciPy</a></button>
-                        <button id="sympy_help"><a href="http://docs.sympy.org/dev/index.html" target="_blank">SymPy</a></button>
+                        <a id="matplotlib_help" href="http://matplotlib.sourceforge.net/" target="_blank">MPL</a>
+                        <a id="scipy_help" href="http://docs.scipy.org/doc/scipy/reference/" target="_blank">SciPy</a>
+                        <a id="sympy_help" href="http://docs.sympy.org/dev/index.html" target="_blank">SymPy</a>
                     </span>
                 </div>
                 <div class="section_row">