diff --git a/.SRCINFO b/.SRCINFO
index d4fab38..8aac00d 100644
--- a/.SRCINFO
+++ b/.SRCINFO
@@ -28,6 +28,7 @@ pkgbase = kwin-effects-forceblur
 	depends = libepoxy
 	depends = libepoxy.so
 	depends = qt6-base=6.10.1
+	optdepends = kwin-x11: for outdated X11 sessions
 	provides = kwin-effects-better-blur
 	source = kwin-effects-forceblur-1.5.0::git+https://github.com/taj-ny/kwin-effects-forceblur.git#tag=v1.5.0
 	source = kwin-effects-forceblur.install
diff --git a/PKGBUILD b/PKGBUILD
index b7cdc49..ba28d72 100644
--- a/PKGBUILD
+++ b/PKGBUILD
@@ -29,6 +29,9 @@ depends=(
     libepoxy libepoxy.so
     'qt6-base=6.10.1'
 )
+optdepends=(
+    'kwin-x11: for outdated X11 sessions'
+)
 makedepends=(
     appstream
     extra-cmake-modules