/usr/lib/GNUstep/SOGo/MailerUI.SOGo/Resources is in sogo-common 2.2.17a-1.1build1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/GNUstep/SOGo/MailerUI.SOGo/../../../../share/GNUstep/SOGo/MailerUI.SOGo/Resources