gworldclock binary package in Ubuntu Jammy amd64

 This program displays the time and date of specified time zones using a
 GTK+ interface. It also provides a "rendezvous" function allowing the zones
 to be synchronised to a time other than the current time. This can help you
 organise meetings across different timezones.
 .
 The time zones may be entered by hand in TZ format or chosen from a list
 prepared from /usr/share/zoneinfo/zone.tab. The zone list is kept in a format
 consistent with the shell script tzwatch.

Source package