I've recently tried to change my default timezone setting for Thunderbird Calendar to "local" as I want my events to be 'floating' and not subject to timezone changes. I did this via the config editor successfully. However, when I start Thunderbird the calendar pane appears with all button's greyed out and appears to be frozen or in a loop trying to refresh the screen and no calendar entries are displayed. It also has a double toolbar (see attached screenshot). The only way to resolve this is to change the timezone back to a non-local setting (in my case 'Australia/Sydney'). Has anyone experienced this problem or have a solution? Below is the prefs.js entry I have been modifying: user_pref("calendar.timezone.local", "Local");