diff --git a/etc-greetd/regreet-session.sh b/etc-greetd/regreet-session.sh
index 6e01461..2dd2d9b 100644
--- a/etc-greetd/regreet-session.sh
+++ b/etc-greetd/regreet-session.sh
@@ -31,4 +31,10 @@ export WLR_NO_HARDWARE_CURSORS=1
 # cage's default is "-m extend", which stretches one canvas across every monitor and
 # leaves ReGreet's login card floating in the middle of the whole multi-monitor span.
 # "-m last" renders on a single output instead, so the card is centred on one screen.
-exec cage -s -m last -- regreet
+#
+# "-d" tells cage to negotiate the xdg-decoration protocol and ask ReGreet not to draw
+# client-side decorations. Without it, ReGreet (GTK4) falls back to its own CSD title
+# bar (move/close chrome) since cage otherwise never offers a decoration mode at all —
+# whether that fallback is visible seems to depend on the host's installed
+# GTK/libdecor versions, so this showed up on some machines and not others.
+exec cage -s -d -m last -- regreet