# Buggy code
def _get_icon_rect(self, opt, text_rect):
    """Get a QRect for the icon to draw.

    Args:
        opt: QStyleOptionTab
        text_rect: The QRect for the text.

    Return:
        A QRect.
    """
    icon_size = opt.iconSize
    if not icon_size.isValid():
        icon_extent = self.pixelMetric(QStyle.PM_SmallIconSize)
        icon_size = QSize(icon_extent, icon_extent)
    icon_mode = QIcon.Normal if opt.state & QStyle.State_Enabled else QIcon.Disabled
    icon_state = QIcon.On if opt.state & QStyle.State_Selected else QIcon.Off
    # reserve space for favicon when tab bar is vertical (issue #1968)
    position = config.val.tabs.position
    if position in [QTabWidget.East, QTabWidget.West] and config.val.tabs.favicons.show:
        tab_icon_size = icon_size
    else:
        actual_size = opt.icon.actualSize(icon_size, icon_mode, icon_state)
        tab_icon_size = QSize(
            min(actual_size.width(), icon_size.width()),
            min(actual_size.height(), icon_size.height()),
        )

    icon_top = text_rect.center().y() + 1 - tab_icon_size.height() / 2
    icon_rect = QRect(QPoint(text_rect.left(), icon_top), tab_icon_size)
    icon_rect = self._style.visualRect(opt.direction, opt.rect, icon_rect)
    return icon_rect


# 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 _get_icon_rect(self, opt, text_rect):
    """Get a QRect for the icon to draw.

    Args:
        opt: QStyleOptionTab
        text_rect: The QRect for the text.

    Return:
        A QRect.
    """
    icon_size = opt.iconSize
    if not icon_size.isValid():
        icon_extent = self.pixelMetric(QStyle.PM_SmallIconSize)
        icon_size = QSize(icon_extent, icon_extent)
    icon_mode = QIcon.Normal if opt.state & QStyle.State_Enabled else QIcon.Disabled
    icon_state = QIcon.On if opt.state & QStyle.State_Selected else QIcon.Off
    # reserve space for favicon when tab bar is vertical (issue #1968)
    position = config.val.tabs.position
    if (
        position in [QTabWidget.East, QTabWidget.West]
        and config.val.tabs.favicons.show != "never"
    ):
        tab_icon_size = icon_size
    else:
        actual_size = opt.icon.actualSize(icon_size, icon_mode, icon_state)
        tab_icon_size = QSize(
            min(actual_size.width(), icon_size.width()),
            min(actual_size.height(), icon_size.height()),
        )

    icon_top = text_rect.center().y() + 1 - tab_icon_size.height() / 2
    icon_rect = QRect(QPoint(text_rect.left(), icon_top), tab_icon_size)
    icon_rect = self._style.visualRect(opt.direction, opt.rect, icon_rect)
    return icon_rect