diff --git a/first_time_install.sh b/first_time_install.sh
index 65cd66fc..ea494c12 100755
--- a/first_time_install.sh
+++ b/first_time_install.sh
@@ -91,7 +91,11 @@ if [ -r "$LM_OS_RELEASE_FILE" ]; then
     DESKTOP_DETECTED=0
     # grep without -q: -q exits at the first match, dpkg then dies of SIGPIPE,
     # and pipefail turns a found desktop into "not found".
-    if dpkg -l | grep -E "^ii.*raspberrypi-ui-mods|^ii.*lxde|^ii.*xfce|^ii.*gnome|^ii.*kde" >/dev/null; then
+    # Match installed package names from their start: the unanchored ".*kde"
+    # matched mid-word (libblockdev-* = "bloc-kde-v") on Lite, and `dpkg -l`
+    # lines also carry descriptions that could match.
+    if dpkg-query -W -f='${db:Status-Abbrev} ${binary:Package}\n' 2>/dev/null \
+            | grep -E "^ii +(raspberrypi-ui-mods|lxde|xfce|gnome|kde)" >/dev/null; then
         DESKTOP_DETECTED=1
     fi
     if systemctl list-units --type=service --state=running 2>/dev/null | grep -qE "lightdm|gdm3|sddm|lxdm"; then