Thunderbird 60.0b3 not displaying Calendar

Using the Thunderbird 60.0b3 with lightning-6.2b3.en-US.xpi and gdata-provider-4.1b3.en-US.win32.xpi from When the addons are installed by a file the option (dragging the file to the addon panel fails) clicking on the Today Pane sidebar or the Calendar icon for the tab does nothing. Any suggestions on what might be the cause?

I filed for this issue.

The current work around is