diff --git a/src/login/test-session-properties.c b/src/login/test-session-properties.c
index 0bfde42213..48aa21abef 100644
--- a/src/login/test-session-properties.c
+++ b/src/login/test-session-properties.c
@@ -1,9 +1,9 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
 /* Usage:
- * ./test-session-properties <SESSION-OBJECT-PATH>
+ * ./test-session-properties <SESSION-OBJECT-PATH> [<TTY>]
  * e.g.,
- * ./test-session-properties /org/freedesktop/login1/session/_32
+ * ./test-session-properties /org/freedesktop/login1/session/_32 /dev/tty2
  */
 
 #include <fcntl.h>
@@ -18,6 +18,8 @@
 #include "terminal-util.h"
 #include "tests.h"
 
+static const char *arg_tty = NULL;
+
 static BusLocator session;
 
 /* Tests org.freedesktop.logind.Session SetType */
@@ -105,10 +107,12 @@ TEST(set_tty) {
         _cleanup_(sd_bus_flush_close_unrefp) sd_bus* bus = NULL;
         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
         _cleanup_free_ char *tty = NULL;
-        const char *path = "/dev/tty2"; /* testsuite uses tty2 */
         int fd;
 
-        fd = open(path, O_RDWR|O_CLOEXEC|O_NOCTTY);
+        if (!arg_tty)
+                return;
+
+        fd = open(arg_tty, O_RDWR|O_CLOEXEC|O_NOCTTY);
         assert_se(fd >= 0);
 
         assert_se(sd_bus_open_system(&bus) >= 0);
@@ -126,6 +130,50 @@ TEST(set_tty) {
         assert_se(streq(tty, "tty2"));
 }
 
+/* Tests org.freedesktop.logind.Session SetIdleHint */
+TEST(set_idle_hint) {
+        _cleanup_(sd_bus_flush_close_unrefp) sd_bus* bus = NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
+        int idle_hint;
+        time_t stamp, idle_since1, idle_since2;
+
+        assert_se(sd_bus_open_system(&bus) >= 0);
+
+        /* Idle hint is not set by default */
+        assert_se(bus_get_property_trivial(bus, &session, "IdleHint", NULL, 'b', &idle_hint) >= 0);
+        assert_se(!idle_hint);
+
+        assert_se(bus_call_method(bus, &session, "TakeControl", NULL, NULL, "b", true) >= 0);
+
+        /* Idle hint can only be set on a graphical session */
+        assert_se(bus_call_method(bus, &session, "SetType", NULL, NULL, "s", "tty") >= 0);
+        assert_se(bus_call_method(bus, &session, "SetIdleHint", &error, NULL, "b", true) < 0);
+        assert_se(sd_bus_error_has_name(&error, SD_BUS_ERROR_NOT_SUPPORTED));
+
+        assert_se(bus_call_method(bus, &session, "SetType", NULL, NULL, "s", "x11") >= 0);
+
+        stamp = now(CLOCK_MONOTONIC);
+
+        /* Idle hint can be set */
+        assert_se(bus_call_method(bus, &session, "SetIdleHint", NULL, NULL, "b", true) >= 0);
+        assert_se(bus_get_property_trivial(bus, &session, "IdleHint", NULL, 'b', &idle_hint) >= 0);
+        assert_se(idle_hint);
+        assert_se(bus_get_property_trivial(bus, &session, "IdleSinceHintMonotonic", NULL, 't', &idle_since1) >= 0);
+        assert_se(idle_since1 >= stamp);
+
+        /* Repeated setting doesn't change anything */
+        assert_se(bus_call_method(bus, &session, "SetIdleHint", NULL, NULL, "b", true) >= 0);
+        assert_se(bus_get_property_trivial(bus, &session, "IdleHint", NULL, 'b', &idle_hint) >= 0);
+        assert_se(idle_hint);
+        assert_se(bus_get_property_trivial(bus, &session, "IdleSinceHintMonotonic", NULL, 't', &idle_since2) >= 0);
+        assert_se(idle_since2 == idle_since1);
+
+        /* Idle hint can be unset */
+        assert_se(bus_call_method(bus, &session, "SetIdleHint", NULL, NULL, "b", false) >= 0);
+        assert_se(bus_get_property_trivial(bus, &session, "IdleHint", NULL, 'b', &idle_hint) >= 0);
+        assert_se(!idle_hint);
+}
+
 static int intro(void) {
         if (saved_argc <= 1)
                 return EXIT_FAILURE;
@@ -136,6 +184,9 @@ static int intro(void) {
                 .interface = "org.freedesktop.login1.Session",
         };
 
+        if (saved_argc > 2)
+                arg_tty = saved_argv[2];
+
         return EXIT_SUCCESS;
 }
 
diff --git a/test/units/testsuite-35.sh b/test/units/testsuite-35.sh
index 78228ab0b2..e9d88e1c83 100755
--- a/test/units/testsuite-35.sh
+++ b/test/units/testsuite-35.sh
@@ -519,7 +519,7 @@ testcase_session_properties() {
     create_session
 
     s=$(loginctl list-sessions --no-legend | awk '$3 == "logind-test-user" { print $1 }')
-    /usr/lib/systemd/tests/unit-tests/manual/test-session-properties "/org/freedesktop/login1/session/_3${s?}"
+    /usr/lib/systemd/tests/unit-tests/manual/test-session-properties "/org/freedesktop/login1/session/_3${s?}" /dev/tty2
 }
 
 testcase_list_users_sessions() {