diff --git a/README.asciidoc b/README.asciidoc
index ef255fb47..60f64133c 100644
--- a/README.asciidoc
+++ b/README.asciidoc
@@ -191,6 +191,7 @@ Contributors, sorted by the number of commits in descending order:
 * Michael Hoang
 * Liam BEGUIN
 * Julie Engel
+* Fritz Reichwald
 * skinnay
 * Zach-Button
 * Tomasz Kramkowski
@@ -199,7 +200,6 @@ Contributors, sorted by the number of commits in descending order:
 * Nikolay Amiantov
 * Ismail S
 * Halfwit
-* Fritz Reichwald
 * David Vogt
 * Claire Cavanaugh
 * rikn00
diff --git a/qutebrowser/commands/userscripts.py b/qutebrowser/commands/userscripts.py
index 3c1d4d89e..960e97318 100644
--- a/qutebrowser/commands/userscripts.py
+++ b/qutebrowser/commands/userscripts.py
@@ -65,9 +65,13 @@ class _QtFIFOReader(QObject):
         """(Try to) read a line from the FIFO."""
         log.procs.debug("QSocketNotifier triggered!")
         self._notifier.setEnabled(False)
-        for line in self._fifo:
-            self.got_line.emit(line.rstrip('\r\n'))
-        self._notifier.setEnabled(True)
+        try:
+            for line in self._fifo:
+                self.got_line.emit(line.rstrip('\r\n'))
+                self._notifier.setEnabled(True)
+        except UnicodeDecodeError as e:
+            log.misc.error("Invalid unicode in userscript output: {}"
+                           .format(e))
 
     def cleanup(self):
         """Clean up so the FIFO can be closed."""
@@ -289,6 +293,9 @@ class _WindowsUserscriptRunner(_BaseUserscriptRunner):
                     self.got_cmd.emit(line.rstrip())
         except OSError:
             log.procs.exception("Failed to read command file!")
+        except UnicodeDecodeError as e:
+            log.misc.error("Invalid unicode in userscript output: {}"
+                           .format(e))
 
         super()._cleanup()
         self.finished.emit()
diff --git a/tests/unit/commands/test_userscripts.py b/tests/unit/commands/test_userscripts.py
index 778270551..5212b0d32 100644
--- a/tests/unit/commands/test_userscripts.py
+++ b/tests/unit/commands/test_userscripts.py
@@ -227,6 +227,24 @@ def test_temporary_files_failed_cleanup(caplog, qtbot, py_proc, runner):
     assert caplog.records[0].message.startswith(expected)
 
 
+def test_unicode_error(caplog, qtbot, py_proc, runner):
+    cmd, args = py_proc(r"""
+        import os
+        with open(os.environ['QUTE_FIFO'], 'wb') as f:
+            f.write(b'\x80')
+    """)
+    with caplog.at_level(logging.ERROR):
+        with qtbot.waitSignal(runner.finished, timeout=10000):
+            runner.prepare_run(cmd, *args)
+            runner.store_text('')
+            runner.store_html('')
+
+    assert len(caplog.records) == 1
+    expected = ("Invalid unicode in userscript output: 'utf-8' codec can't "
+                "decode byte 0x80 in position 0: invalid start byte")
+    assert caplog.records[0].message == expected
+
+
 def test_unsupported(monkeypatch, tabbed_browser_stubs):
     monkeypatch.setattr(userscripts.os, 'name', 'toaster')
     with pytest.raises(userscripts.UnsupportedError) as excinfo: