diff --git a/kde-frameworks/kwindowsystem/Manifest b/kde-frameworks/kwindowsystem/Manifest
index e10dd869fa478..67e04bb35c3f3 100644
--- a/kde-frameworks/kwindowsystem/Manifest
+++ b/kde-frameworks/kwindowsystem/Manifest
@@ -1,3 +1,4 @@
 DIST kwindowsystem-5.116.0.tar.xz 2406688 BLAKE2B 99bb7ec3d3302543bab77a526c860f8c13233c803b92e15a225fbecdd74ca2498b0f9a58a1c310c84eb81b07cf8b586dfb0388cc45da65c38d501a774ecbe637 SHA512 1b8d45ee0a09161b45f62e6ba4f200f3c2ad937c20eedc03bf65c3a788a5311727ec2a1634db9e1b1208b8ecbe4158273d11c97924a86059a06d3a24d1201157
 DIST kwindowsystem-6.18.0.tar.xz 2362868 BLAKE2B 3c2bb34b7f7429779c970b73b54a7d86b3fa9aa5186bf3fbedcefea01db850150d007d634afb818d6b62025c8354af5f3da11c2b8223ab52d2f35f87e5aa1758 SHA512 214e090834ee11388daa07b79699c55152797ef6208f01cb4b883feb26c6c731f3cba9800cbb74ad8c020379ab32392bc5c25e9888b8ee726f70be30a26ef15a
 DIST kwindowsystem-6.20.0.tar.xz 2363808 BLAKE2B 2aba8efb56a8d32ea1da174786dca90dfc50c8b466229451fbb0fa928c256ecb0c96ecadefd91dd889a30fc56c147978a6abc229bec9b3563d5cfd6491c818e1 SHA512 3c7c8b144e5c9779458fa4dfebe8d67611fa3cfbc7a9b46e327ef570760f13477e19f4d4a41fa8e71ab8f5643268ddd39e243e127727c11f311b60412389d91c
+DIST kwindowsystem-6.21.0.tar.xz 2363496 BLAKE2B 1bf33aa2c5e1adda72403db5457222df599f0a117cc469646e3d334f684692dee3638c7888b0146f1bb5a31e2963dd1117ab678eccd2c0cd5dd3a9098ae2406c SHA512 b55c8e5a01a88312c7e74d2f93b0a7159619dff1a3b1efc8f419b97fa12aafdee5f198cd7b6a3c935dffb02fffb8738ce01b26edd93f0d2343d603e3dd2dfebb
diff --git a/kde-frameworks/kwindowsystem/kwindowsystem-6.21.0.ebuild b/kde-frameworks/kwindowsystem/kwindowsystem-6.21.0.ebuild
new file mode 100644
index 0000000000000..ecfc47e77e7af
--- /dev/null
+++ b/kde-frameworks/kwindowsystem/kwindowsystem-6.21.0.ebuild
@@ -0,0 +1,53 @@
+# Copyright 1999-2025 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+QTMIN=6.8.1
+inherit ecm frameworks.kde.org
+
+DESCRIPTION="Framework providing access to properties and features of the window manager"
+
+LICENSE="|| ( LGPL-2.1 LGPL-3 ) MIT"
+KEYWORDS="~amd64 ~arm64 ~loong ~ppc64 ~riscv ~x86"
+IUSE="wayland X"
+
+RESTRICT="test"
+
+# slot op: Uses Qt6::GuiPrivate for qtx11extras_p.h
+# slot op: Uses private/qwayland*_p.h headers
+# x11-base/xorg-proto: X11/Xlib.h included in public header kkeyserver.h,
+#   req. by KF6WindowSystemConfig.cmake; see also bug #939177
+RDEPEND="
+	>=dev-qt/qtbase-${QTMIN}:6[gui]
+	>=dev-qt/qtdeclarative-${QTMIN}:6
+	wayland? ( >=dev-qt/qtbase-${QTMIN}:6=[wayland] )
+	X? (
+		>=dev-qt/qtbase-${QTMIN}:6=[gui,X]
+		x11-base/xorg-proto
+		x11-libs/libX11
+		x11-libs/libXfixes
+		x11-libs/libxcb
+		x11-libs/xcb-util-keysyms
+	)
+"
+DEPEND="${RDEPEND}
+	test? ( >=dev-qt/qtbase-${QTMIN}:6[widgets] )
+	wayland? (
+		dev-libs/plasma-wayland-protocols
+		>=dev-libs/wayland-protocols-1.21
+	)
+"
+RDEPEND+=" wayland? ( || ( >=dev-qt/qtbase-6.10:6[wayland] <dev-qt/qtwayland-6.10:6 ) )"
+BDEPEND=">=dev-qt/qttools-${QTMIN}:6[linguist]"
+
+DOCS=( docs/README.kstartupinfo )
+
+src_configure() {
+	local mycmakeargs=(
+		-DKWINDOWSYSTEM_WAYLAND=$(usex wayland)
+		-DKWINDOWSYSTEM_X11=$(usex X)
+	)
+
+	ecm_src_configure
+}