diff --git a/src/wcm.cpp b/src/wcm.cpp
index ed998c0..3f8985a 100644
--- a/src/wcm.cpp
+++ b/src/wcm.cpp
@@ -1,6 +1,8 @@
 #include "wcm.hpp"
 #include "utils.hpp"
+#include "ipc.hpp"
 #include "config-merge.hpp"
+#include <set>
 
 #include <filesystem>
 #include <fmt/format.h>
@@ -615,15 +617,55 @@ OptionWidget::OptionWidget(Option *option) : Gtk::Box(Gtk::ORIENTATION_HORIZONTA
         } else
         {
             auto combo_box = std::make_unique<Gtk::ComboBoxText>();
+            std::set<std::string> values;
             for (const auto & [name, str_value] : option->str_labels)
             {
                 combo_box->append(str_value, name);
+                values.insert(str_value);
                 if (str_value == wf_option->get_value_str())
                 {
                     combo_box->set_active_id(str_value);
                 }
             }
 
+            if (option->plugin->name == "wayfire-lock" && option->name == "lock_output")
+            {
+                // Preserve the saved/offline choice. Discovery only appends
+                // physical heads and never emits a selection/save operation.
+                auto selected = wf_option->get_value_str();
+                if (values.insert(selected).second)
+                    combo_box->append(selected, selected + " (disconnected)");
+                combo_box->set_active_id(selected);
+                auto known = std::make_shared<std::set<std::string>>(values);
+                signal_map().connect([this, widget = combo_box.get(), known]
+                {
+                    discovery.send("window-rules/list-outputs", {}, [widget, known] (WcmIpcResult result)
+                    {
+                        if (!result.error.empty())
+                        {
+                            widget->set_tooltip_text("Monitor discovery: " + result.error + ". The saved choice is retained.");
+                            return;
+                        }
+                        auto outputs = result.reply;
+                        for (size_t i = 0; i < outputs.size(); ++i)
+                        {
+                            auto output = outputs[i];
+                            auto append = [&] (const wf::json_reference_t& head)
+                            {
+                                auto name = head["name"].as_string();
+                                if (!name.empty() && known->insert(name).second) widget->append(name, name);
+                            };
+                            if (output.has_member("members") && output["members"].size())
+                            {
+                                auto members = output["members"];
+                                for (size_t j = 0; j < members.size(); ++j) append(members[j]);
+                            } else append(output);
+                        }
+                    });
+                });
+                signal_unmap().connect([this] { discovery.cancel_observation(); });
+            }
+
             combo_box->signal_changed().connect(
                 [=, widget = combo_box.get()]
                 {