xcal 4.1-19build1 (s390x binary) in ubuntu focal

 The "classic" calendar app with memos and alarms, xcal normally
 sits idle and displays the date. When clicked on, pops up a `strip'
 for this month. Clicking on a day allows you to enter details.
 Automatically parses times entered, and reminds you 5 minutes
 before your appointment.
 .
 Supports daily and weekly repeating events and context-sensitive help.