diff --git a/man/org.freedesktop.login1.xml b/man/org.freedesktop.login1.xml
index 2c1b9118ea..ba1614be4e 100644
--- a/man/org.freedesktop.login1.xml
+++ b/man/org.freedesktop.login1.xml
@@ -1161,7 +1161,6 @@ node /org/freedesktop/login1/session/1 {
       readonly (so) Seat = ...;
       @org.freedesktop.DBus.Property.EmitsChangedSignal("const")
       readonly s TTY = '...';
-      @org.freedesktop.DBus.Property.EmitsChangedSignal("const")
       readonly s Display = '...';
       @org.freedesktop.DBus.Property.EmitsChangedSignal("const")
       readonly b Remote = ...;
diff --git a/src/libsystemd/sd-journal/sd-journal.c b/src/libsystemd/sd-journal/sd-journal.c
index eb35b9d9c4..f2b7a379c0 100644
--- a/src/libsystemd/sd-journal/sd-journal.c
+++ b/src/libsystemd/sd-journal/sd-journal.c
@@ -3121,8 +3121,9 @@ _public_ int sd_journal_query_unique(sd_journal *j, const char *field) {
 
         assert_return(j, -EINVAL);
         assert_return(!journal_origin_changed(j), -ECHILD);
-        assert_return(!isempty(field), -EINVAL);
-        assert_return(field_is_valid(field), -EINVAL);
+
+        if (!field_is_valid(field))
+                return -EINVAL;
 
         r = free_and_strdup(&j->unique_field, field);
         if (r < 0)
diff --git a/src/login/logind-session-dbus.c b/src/login/logind-session-dbus.c
index d9d6cb2856..ad4e5c5f6d 100644
--- a/src/login/logind-session-dbus.c
+++ b/src/login/logind-session-dbus.c
@@ -875,7 +875,7 @@ static const sd_bus_vtable session_vtable[] = {
         SD_BUS_PROPERTY("VTNr", "u", NULL, offsetof(Session, vtnr), SD_BUS_VTABLE_PROPERTY_CONST),
         SD_BUS_PROPERTY("Seat", "(so)", property_get_seat, 0, SD_BUS_VTABLE_PROPERTY_CONST),
         SD_BUS_PROPERTY("TTY", "s", NULL, offsetof(Session, tty), SD_BUS_VTABLE_PROPERTY_CONST),
-        SD_BUS_PROPERTY("Display", "s", NULL, offsetof(Session, display), SD_BUS_VTABLE_PROPERTY_CONST),
+        SD_BUS_PROPERTY("Display", "s", NULL, offsetof(Session, display), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
         SD_BUS_PROPERTY("Remote", "b", bus_property_get_bool, offsetof(Session, remote), SD_BUS_VTABLE_PROPERTY_CONST),
         SD_BUS_PROPERTY("RemoteHost", "s", NULL, offsetof(Session, remote_host), SD_BUS_VTABLE_PROPERTY_CONST),
         SD_BUS_PROPERTY("RemoteUser", "s", NULL, offsetof(Session, remote_user), SD_BUS_VTABLE_PROPERTY_CONST),