Install this version:
emerge -a =app-emacs/supersonic-0.7.4
If this version is masked, you can unmask it using the autounmask tool or standard emerge options:
autounmask =app-emacs/supersonic-0.7.4
Or alternatively:
emerge --autounmask-write -a =app-emacs/supersonic-0.7.4
# automatically generated by g-sorcery
# please do not edit this file
EAPI=8
REPO_URI="https://stable.melpa.org/packages/"
SOURCE_TYPE="tar"
REALNAME="supersonic"
DIGEST_SOURCES="yes"
inherit g-sorcery gs-elpa
DESCRIPTION="Music client for Subsonic servers and Music Assistant"
HOMEPAGE="https://github.com/systemfreund/supersonic.el"
SRC_URI="${REPO_URI}${REALNAME}-${PV}.${SUFFIX}"
SLOT="0"
KEYWORDS="~amd64 ~x86"
DEPEND="app-emacs/transient
app-emacs/emacs-aio"
RDEPEND="app-emacs/transient
app-emacs/emacs-aio"
app-emacs/transient app-emacs/emacs-aio
app-emacs/transient app-emacs/emacs-aio