Qt4 is dead and going away. To keep this package in tree, it will need to be ported to Qt5. Debian have apparently been able to do it with a patch, see url.
The bug has been referenced in the following commit(s):
Author: Andreas Sturmlechner <email@example.com>
AuthorDate: 2018-03-04 16:03:15 +0000
Commit: Andreas Sturmlechner <firstname.lastname@example.org>
CommitDate: 2018-03-04 17:29:39 +0000
sci-biology/clustalx: Switch to Qt5
Thanks to Debian.
Package-Manager: Portage-2.3.24, Repoman-2.3.6
sci-biology/clustalx/clustalx-2.1-r3.ebuild | 56 ++++
sci-biology/clustalx/files/clustalx-2.1-qt5.patch | 295 ++++++++++++++++++++++
2 files changed, 351 insertions(+)}
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An automated check of this bug succeeded - the previous repoman errors are now resolved.
x86 stable, closing