Seems like the dependency on QtUiTools was removed in https://github.com/musescore/MuseScore/commit/d82c475247282b3cf6b0a0b139f60bc96b0325dd. The dev-qt/designer:5 dependency isn't used anymore, everything works fine w/o it.
The bug has been closed via the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=3b3bfc07477a9f2f4f18e20bea8287584c6e41a5 commit 3b3bfc07477a9f2f4f18e20bea8287584c6e41a5 Author: Violet Purcell <vimproved@inventati.org> AuthorDate: 2024-01-25 01:02:14 +0000 Commit: Sam James <sam@gentoo.org> CommitDate: 2024-01-25 01:14:57 +0000 media-sound/musescore: remove stale dev-qt/designer dependency Closes: https://bugs.gentoo.org/917352 Signed-off-by: Violet Purcell <vimproved@inventati.org> Closes: https://github.com/gentoo/gentoo/pull/34999 Signed-off-by: Sam James <sam@gentoo.org> media-sound/musescore/musescore-4.0.2-r1.ebuild | 1 - media-sound/musescore/musescore-4.2.1-r1.ebuild | 1 - media-sound/musescore/musescore-9999.ebuild | 1 - 3 files changed, 3 deletions(-)