Make a copy of the iterator to avoid "OrderedDict mutated" error

Closes readthedocs#19

Author: humitos

hoverxref/extension.py

@@ -76,7 +76,8 @@ def setup_sphinx_tabs(app, config):
     Sphinx Tabs removes the CSS/JS from pages that does not use the directive.
     Although, we need them to use inside the tooltip.
     """
-    for listener_id, function in app.events.listeners.get('html-page-context').items():
+    listeners = list(app.events.listeners.get('html-page-context').items())
+    for listener_id, function in listeners:
         module_name = inspect.getmodule(function).__name__
         if module_name == 'sphinx_tabs.tabs':
             app.disconnect(listener_id)