Trying to update from Plasma 5's Discover with flatpak support to Discover 6 with Flatpak has a dependency conflict with dev-libs/appstream (dependency 1) from being able to update because Flatpak (dependency 2) requires a specific version of appstream: ----- !!! Multiple package instances within a single package slot have been pulled !!! into the dependency graph, resulting in a slot conflict: dev-libs/appstream:0 (dev-libs/appstream-0.16.4:0/4::gentoo, ebuild scheduled for merge) USE="introspection -apt -doc -qt5 -systemd -test" ABI_X86="(64)" pulled in by >=dev-libs/appstream-0.12:0/4= required by (sys-apps/flatpak-1.14.4-r3:0/0::gentoo, installed) USE="X policykit seccomp -doc -introspection -systemd" ABI_X86="(64)" ^^^^^ (dev-libs/appstream-1.0.2:0/5::gentoo, ebuild scheduled for merge) USE="introspection qt6 -apt -doc -systemd -test" ABI_X86="(64)" pulled in by >=dev-libs/appstream-1.0.0:=[qt6] required by (kde-plasma/discover-6.0.1:6/6::gentoo, ebuild scheduled for merge) USE="firmware flatpak telemetry -debug -snap -test -webengine" ABI_X86="(64)"
The dependency inside flatpak ebuild is >=dev-libs/appstream-0.12:=, so this is an incorrect assumption.