# Buggy code
def load_items(self, items):
    stream, _data, user_data = tabhistory.serialize(items)
    qtutils.deserialize_stream(stream, self._history)
    for i, data in enumerate(user_data):
        self._history.itemAt(i).setUserData(data)
    cur_data = self._history.currentItem().userData()
    if cur_data is not None:
        if "zoom" in cur_data:
            self._tab.zoom.set_factor(cur_data["zoom"])
        if "scroll-pos" in cur_data and self._tab.scroller.pos_px() == QPoint(0, 0):
            QTimer.singleShot(
                0,
                functools.partial(self._tab.scroller.to_point, cur_data["scroll-pos"]),
            )


# Traceback (ValueError)
16:39:44 DEBUG    init       app:_init_modules:468 Initializing websettings...
16:39:45 ERROR    misc       crashsignal:exception_hook:216 Uncaught exception
Traceback (most recent call last):
File "/bin/qutebrowser", line 11, in <module>
load_entry_point('qutebrowser==1.1.1', 'gui_scripts', 'qutebrowser')()
File "/usr/lib/python3.6/site-packages/qutebrowser/qutebrowser.py", line 188, in main
return app.run(args)
File "/usr/lib/python3.6/site-packages/qutebrowser/app.py", line 137, in run
init(args, crash_handler)
File "/usr/lib/python3.6/site-packages/qutebrowser/app.py", line 163, in init
_init_modules(args, crash_handler)
File "/usr/lib/python3.6/site-packages/qutebrowser/app.py", line 469, in _init_modules
websettings.init(args)
File "/usr/lib/python3.6/site-packages/qutebrowser/config/websettings.py", line 215, in init
webenginesettings.init(args)
File "/usr/lib/python3.6/site-packages/qutebrowser/browser/webengine/webenginesettings.py", line 297, in init
websettings.init_mappings(MAPPINGS)
File "/usr/lib/python3.6/site-packages/qutebrowser/config/websettings.py", line 198, in init_mappings
mapping.set(value)
File "/usr/lib/python3.6/site-packages/qutebrowser/config/websettings.py", line 72, in set
self._set(value, settings=settings)
File "/usr/lib/python3.6/site-packages/qutebrowser/browser/webengine/webenginesettings.py", line 154, in _set
filenames = [self._find_installed(code) for code in value]
File "/usr/lib/python3.6/site-packages/qutebrowser/browser/webengine/webenginesettings.py", line 154, in <listcomp>
filenames = [self._find_installed(code) for code in value]
File "/usr/lib/python3.6/site-packages/qutebrowser/browser/webengine/webenginesettings.py", line 143, in _find_installed
local_filename = spell.local_filename(code)
File "/usr/lib/python3.6/site-packages/qutebrowser/browser/webengine/spell.py", line 64, in local_filename
all_installed = local_files(code)
File "/usr/lib/python3.6/site-packages/qutebrowser/browser/webengine/spell.py", line 51, in local_files
for matching_dict in sorted(matching_dicts, key=version, reverse=True):
File "/usr/lib/python3.6/site-packages/qutebrowser/browser/webengine/spell.py", line 36, in version
.format(filename))
ValueError: the given dictionary file name is malformed: /usr/share/qt/qtwebengine_dictionaries/en-US.bdic

# Fixed code
def load_items(self, items):
    if items:
        self._tab.predicted_navigation.emit(items[-1].url)

    stream, _data, user_data = tabhistory.serialize(items)
    qtutils.deserialize_stream(stream, self._history)
    for i, data in enumerate(user_data):
        self._history.itemAt(i).setUserData(data)
    cur_data = self._history.currentItem().userData()
    if cur_data is not None:
        if "zoom" in cur_data:
            self._tab.zoom.set_factor(cur_data["zoom"])
        if "scroll-pos" in cur_data and self._tab.scroller.pos_px() == QPoint(0, 0):
            QTimer.singleShot(
                0,
                functools.partial(self._tab.scroller.to_point, cur_data["scroll-pos"]),
            )