gui-apps/qtgreet fails to build

[Paulo-B]

The QTGreet for greetd fails to build as of now. With the following error:

!!! All ebuilds that could satisfy "qtgreet" have been masked.
!!! One of the following masked packages is required to complete your request:
- gui-apps/qtgreet-9999::wayland-desktop (masked by: missing keyword, invalid: DEPEND: Improper context for slot-operator "built" atom syntax: gui-libs/wlroots:0/18=, invalid: RDEPEND: Improper context for slot-operator "built" atom syntax: gui-libs/wlroots:0/18=)
- gui-apps/qtgreet-2.0.2::wayland-desktop (masked by: invalid: DEPEND: Improper context for slot-operator "built" atom syntax: gui-libs/wlroots:0/17=, invalid: RDEPEND: Improper context for slot-operator "built" atom syntax: gui-libs/wlroots:0/17=)