Calendar:Lightning:0.1:Known Issues

Data loss

• Dragging events that span more than one day will shorten the event duration (bug 323696). Workaround: change the time of an event that spans more than one day by double-clicking it and manually editing the start and end times in the dialog box.
• On Windows, events sometimes show up at the wrong times if you have "Automatically adjust clock for daylight saving changes" unchecked in the Timezone tab of the Date and Time control panel (bug 326868). Workaround: check the "Automatically adjust clock for daylight saving changes" box.
• Shutting down Thunderbird does not wait for pending calendar writes to complete, which could cause calendar corruption. Workaround: wait 5 seconds after the last calendar modification before exiting Thunderbird (bug 328810).
• Lightning behaves unreliably with dates before 1970 or after 2037; failure modes may include JavaScript exceptions and crashes (bug 278236). Workaround: don't enter such dates.

Data loss when editing or importing non-Lightning ICS data

Lightning is not really ready to be used to modify ICS data that it did not itself generate. If you decide that you want to do this anyway, here are some things to be aware of:

• Editing events causes them to be put into your default timezone (bug 304486).
• VALARM support is not yet complete (bug 308538). Importing or modifying calendars that contain VALARMs created by other programs will either fail or strip out any non-understood data.
• VTIMEZONE data produced by programs other than Lightning will be generally be read and understood, and should in theory be preserved, but this is not well tested (bug 314339).
• VEVENTs with a DURATION but no DTEND are converted to DTSTART+DTEND-style events upon importing or editing a calendar that contains them (bug 317786).
• Inline attachments and attachment parameters will either cause errors or be stripped out when importing or editing a calendar that contains them (bug 319909).
• X- components are stripped out when editing or importing a calendar that contains them (bug 322837).
• X- parameters are stripped out when editing or importing a calendar that contains them (bug 322831).

Surprising Behavior

• Delete a local calendar. Create a new one. The old events show up in the new calendar (bug 296202). Workaround: create the new calendar before deleting the old one.
• On Windows, Lightning doesn't work if the path to your profile directory has non-ASCII characters in it (bug 324311). Workaround: create a separate profile in a directory that has only ASCII characters in the path.
• Editing recurring tasks is currently disabled to avoid dataloss issues (bug 328197).
• Some failures when creating or viewing a calendar for the first time do not display an error dialog, though information is available in the JavaScript console (bug 328618).
• Default timezone guessing is unreliable, especially in the southern hemisphere (bug 328996). Note that all events that you edit or create will end up in the default timezone. Workaround: manually set your timezone in the Lightning panel of the Options or Preferences dialog.

CalDAV bugs

• There is no UI to specify a username and password for a CalDAV account (bug 308567). Workaround: specify both the username and password in the calendar URI. Note that this workaround is a poor idea from a security standpoint. Be sure to URL-encode appropriate characters (e.g. the @ symbol).
• Editing recurring items may fail or lose data (bug 327990, bug 328576). No workaround known.