Launchpad currently recommends translating gfxboot-theme-ubuntu in Ubuntu Jammy.

Template "bootloader" in Ubuntu Jammy package "gfxboot-theme-ubuntu"

Language Status Untranslated Need review Changed Last Edited By
Cherokee 100.00  100.0% untranslated 118 118 14 14 0 2013-06-17 19:39:40 UTC
Dakota 100.00  100.0% untranslated 118 118 0 0
Hawaiian 100.00  100.0% untranslated 118 118 0 0 2011-07-31 18:55:40 UTC
Inuktitut 077.12  22.88135593220339% translated  77.11864406779661% untranslated 91 91 0 0 2013-04-29 15:38:13 UTC Thomassie Mangiok
Lakota 100.00  100.0% untranslated 118 118 0 0
Louisiana French 100.00  100.0% untranslated 118 118 0 0
Ojibwe 044.92  55.08474576271186% translated  44.91525423728814% untranslated 53 53 0 0 2020-01-27 21:55:31 UTC Travis Jordan
Pennsylvania German 100.00  100.0% untranslated 118 118 0 0
Spanish 000.00  100.0% translated 0 0 15 15 2020-04-08 08:37:30 UTC Ricardo Pérez López
Tlingit 100.00  100.0% untranslated 118 118 0 0
Yiddish 096.61  3.389830508474576% translated  96.61016949152543% untranslated 114 114 89 89 0 2009-10-14 14:29:32 UTC Janis96
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Key to this table: “Unchanged” means Translated
and “untranslated” means just that, Untranslated

Other versions of gfxboot-theme-ubuntu in Ubuntu