Syncing sometimes doesn't fire on a regular basis. Workaround: click 'force event sync' in the settings page.
Occasionally the new tab page flashes
Sign in with Google for a second before showing events.
Status: This was fixed in version 0.0.11.
Some users have reported that clicking
Sign in with Google doesn't show a log in screen, and that checking the browser's console shows an error that "Service has been disabled for this account."
Status: This was fixed on April 2, after Google approved the full API scopes for Up Next.
Settings page doesn't have a loader after signing in, which means it's confusing/unclear when you're trying to select a calendar for the first time. Status: Fixed in 0.0.10. Workaround: Wait a few seconds for the calendar list to populate.