Launchpad currently recommends translating gnome-desktop3 in Ubuntu Bionic.

Template "gnome-desktop-3.0" in Ubuntu Bionic package "gnome-desktop3"

Language Status Untranslated Need review Changed Last Edited By
Cherokee 100.00  100.0% untranslated 23 23 0 0
Dakota 100.00  100.0% untranslated 23 23 0 0
Hawaiian 100.00  100.0% untranslated 23 23 0 0
Inuktitut 100.00  100.0% untranslated 23 23 0 0
Lakota 100.00  100.0% untranslated 23 23 0 0
Ojibwe 100.00  100.0% untranslated 23 23 0 0
Spanish 000.00  100.0% translated 0 0 2 2 2018-05-17 21:26:36 UTC 2018-05-17 Daniel Mustieles
Tlingit 100.00  100.0% untranslated 23 23 0 0
Yiddish 100.00  100.0% untranslated 23 23 0 0 2018-05-17 21:26:33 UTC 2018-05-17 Raphael Finkel
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Key to this table: “Unchanged” means Translated
and “untranslated” means just that, Untranslated

Other versions of gnome-desktop3 in Ubuntu