# Buggy code
def set_mode_active(self, mode, val):
    """Setter for self.{insert,command,caret}_active.

    Re-set the stylesheet after setting the value, so everything gets
    updated by Qt properly.
    """
    if mode == usertypes.KeyMode.insert:
        log.statusbar.debug("Setting insert flag to {}".format(val))
        self._color_flags.insert = val
    if mode == usertypes.KeyMode.passthrough:
        log.statusbar.debug("Setting passthrough flag to {}".format(val))
        self._color_flags.passthrough = val
    if mode == usertypes.KeyMode.command:
        log.statusbar.debug("Setting command flag to {}".format(val))
        self._color_flags.command = val
    elif mode in [usertypes.KeyMode.prompt, usertypes.KeyMode.yesno]:
        log.statusbar.debug("Setting prompt flag to {}".format(val))
        self._color_flags.prompt = val
    elif mode == usertypes.KeyMode.caret:
        tab = self._current_tab()
        log.statusbar.debug(
            "Setting caret flag - val {}, selection {}".format(
                val, tab.caret.selection_enabled
            )
        )
        if val:
            if tab.caret.selection_enabled:
                self._set_mode_text("{} selection".format(mode.name))
                self._color_flags.caret = ColorFlags.CaretMode.selection
            else:
                self._set_mode_text(mode.name)
                self._color_flags.caret = ColorFlags.CaretMode.on
        else:
            self._color_flags.caret = ColorFlags.CaretMode.off
    config.set_register_stylesheet(self, update=False)


# 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 set_mode_active(self, mode, val):
    """Setter for self.{insert,command,caret}_active.

    Re-set the stylesheet after setting the value, so everything gets
    updated by Qt properly.
    """
    if mode == usertypes.KeyMode.insert:
        log.statusbar.debug("Setting insert flag to {}".format(val))
        self._color_flags.insert = val
    if mode == usertypes.KeyMode.passthrough:
        log.statusbar.debug("Setting passthrough flag to {}".format(val))
        self._color_flags.passthrough = val
    if mode == usertypes.KeyMode.command:
        log.statusbar.debug("Setting command flag to {}".format(val))
        self._color_flags.command = val
    elif mode in [usertypes.KeyMode.prompt, usertypes.KeyMode.yesno]:
        log.statusbar.debug("Setting prompt flag to {}".format(val))
        self._color_flags.prompt = val
    elif mode == usertypes.KeyMode.caret:
        if not val:
            # Turning on is handled in on_current_caret_selection_toggled
            log.statusbar.debug("Setting caret mode off")
            self._color_flags.caret = ColorFlags.CaretMode.off
    config.set_register_stylesheet(self, update=False)