From f787f004afce5511d0c2eb0ebef18f860f322062 Mon Sep 17 00:00:00 2001
From: Florian Bruhin <git@the-compiler.org>
Date: Fri, 18 Dec 2015 20:23:39 +0100
Subject: [PATCH] Fix _BaseUserscriptRunner when env is None.

---
 qutebrowser/commands/userscripts.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/qutebrowser/commands/userscripts.py b/qutebrowser/commands/userscripts.py
index 6931dce0a..00f7d2b1f 100644
--- a/qutebrowser/commands/userscripts.py
+++ b/qutebrowser/commands/userscripts.py
@@ -108,7 +108,8 @@ class _BaseUserscriptRunner(QObject):
             verbose: Show notifications when the command started/exited.
         """
         self._env = {'QUTE_FIFO': self._filepath}
-        self._env.update(env)
+        if env is not None:
+            self._env.update(env)
         self._proc = guiprocess.GUIProcess(self._win_id, 'userscript',
                                            additional_env=self._env,
                                            verbose=verbose, parent=self)