diff --git a/panels/dock/taskmanager/CMakeLists.txt b/panels/dock/taskmanager/CMakeLists.txt
index 37aa7a1a4..a23567751 100644
--- a/panels/dock/taskmanager/CMakeLists.txt
+++ b/panels/dock/taskmanager/CMakeLists.txt
@@ -78,6 +78,8 @@ add_library(dock-taskmanager SHARED ${DBUS_INTERFACES}
     hoverpreviewproxymodel.h
     taskmanager.cpp
     taskmanager.h
+    foldermenuregistry.cpp
+    foldermenuregistry.h
     treelandwindow.cpp
     treelandwindow.h
     treelandwindowmonitor.cpp
diff --git a/panels/dock/taskmanager/foldermenuregistry.cpp b/panels/dock/taskmanager/foldermenuregistry.cpp
new file mode 100644
index 000000000..458dab261
--- /dev/null
+++ b/panels/dock/taskmanager/foldermenuregistry.cpp
@@ -0,0 +1,90 @@
+// SPDX-FileCopyrightText: 2026 UnionTech Software Technology Co., Ltd.
+// SPDX-License-Identifier: GPL-3.0-or-later
+#include "foldermenuregistry.h"
+
+#include <QCoreApplication>
+#include <QMetaMethod>
+#include <QSet>
+
+namespace dock {
+namespace {
+const QString OpenFolder = QStringLiteral("open-folder");
+const QString UndockFolder = QStringLiteral("undock-folder");
+}
+
+FolderMenuRegistry::FolderMenuRegistry(QObject *parent) : QObject(parent) {}
+
+bool FolderMenuRegistry::registerProvider(const QString &folderType, QObject *provider)
+{
+    if (folderType.trimmed().isEmpty() || !provider || provider->thread() != thread()) return false;
+    const auto meta = provider->metaObject();
+    const int actions = meta->indexOfMethod("folderMenuActions(QString)");
+    const int trigger = meta->indexOfMethod("triggerFolderMenuAction(QString,QString)");
+    if (actions < 0 || trigger < 0 || meta->method(actions).returnType() != QMetaType::QVariantList
+        || meta->method(trigger).returnType() != QMetaType::Void) return false;
+    // A different plugin may not silently replace a registered source.
+    const auto existing = m_providers.value(folderType);
+    if (existing && existing != provider) return false;
+    m_providers.insert(folderType, provider);
+    return true;
+}
+
+void FolderMenuRegistry::unregisterProvider(const QString &folderType, QObject *provider)
+{
+    if (provider && m_providers.value(folderType) == provider) m_providers.remove(folderType);
+}
+
+QVariantList FolderMenuRegistry::standardItems(const QString &folderName)
+{
+    return {QVariantMap{{"id", OpenFolder}, {"name", folderName}},
+            QVariantMap{{"id", UndockFolder}, {"name", QCoreApplication::translate("FolderContextMenu", "Undock")}}};
+}
+
+QVariantList FolderMenuRegistry::customItems(QObject *provider, const QString &folderId) const
+{
+    QVariantList supplied;
+    if (!provider || folderId.isEmpty()
+        || !QMetaObject::invokeMethod(provider, "folderMenuActions", Qt::DirectConnection,
+                                      Q_RETURN_ARG(QVariantList, supplied), Q_ARG(QString, folderId))) return {};
+    QVariantList items;
+    QSet<QString> used{OpenFolder, UndockFolder};
+    for (const auto &value : supplied) {
+        const auto item = value.toMap();
+        const QString id = item.value("id").toString();
+        const QString name = item.value("name").toString();
+        if (id.trimmed().isEmpty() || name.trimmed().isEmpty() || used.contains(id)
+            || !item.value("visible", true).toBool()) continue;
+        used.insert(id);
+        const bool checkable = item.value("checkable", false).toBool();
+        items.append(QVariantMap{{"id", id}, {"name", name},
+                                 {"enabled", item.value("enabled", true).toBool()},
+                                 {"checkable", checkable},
+                                 {"checked", checkable && item.value("checked", false).toBool()}});
+    }
+    return items;
+}
+
+QVariantList FolderMenuRegistry::menuItems(const QString &folderType, const QString &folderId, const QString &folderName) const
+{
+    auto items = standardItems(folderName);
+    items.append(customItems(m_providers.value(folderType), folderId));
+    return items;
+}
+
+bool FolderMenuRegistry::trigger(const QString &folderType, const QString &folderId, const QString &actionId) const
+{
+    const QPointer<QObject> provider = m_providers.value(folderType);
+    if (!provider || actionId == OpenFolder || actionId == UndockFolder) return false;
+    // Revalidate at click time: a plugin may unload or disable an action while
+    // its native menu is open. Never dispatch arbitrary or stale action IDs.
+    const auto items = customItems(provider, folderId);
+    if (!provider || m_providers.value(folderType) != provider) return false;
+    for (const auto &value : items) {
+        const auto item = value.toMap();
+        if (item.value("id").toString() != actionId || !item.value("enabled").toBool()) continue;
+        return QMetaObject::invokeMethod(provider, "triggerFolderMenuAction", Qt::DirectConnection,
+                                         Q_ARG(QString, folderId), Q_ARG(QString, actionId));
+    }
+    return false;
+}
+}
diff --git a/panels/dock/taskmanager/foldermenuregistry.h b/panels/dock/taskmanager/foldermenuregistry.h
new file mode 100644
index 000000000..93ce5f5a4
--- /dev/null
+++ b/panels/dock/taskmanager/foldermenuregistry.h
@@ -0,0 +1,31 @@
+// SPDX-FileCopyrightText: 2026 UnionTech Software Technology Co., Ltd.
+// SPDX-License-Identifier: GPL-3.0-or-later
+#pragma once
+
+#include <QHash>
+#include <QObject>
+#include <QPointer>
+#include <QVariant>
+
+namespace dock {
+
+// Optional menu extensions owned by folder-source plugins. Providers remain
+// owned by their plugin and expose the two invokables documented in docs/.
+class FolderMenuRegistry : public QObject
+{
+    Q_OBJECT
+public:
+    explicit FolderMenuRegistry(QObject *parent = nullptr);
+
+    bool registerProvider(const QString &folderType, QObject *provider);
+    void unregisterProvider(const QString &folderType, QObject *provider);
+    static QVariantList standardItems(const QString &folderName);
+    QVariantList menuItems(const QString &folderType, const QString &folderId, const QString &folderName) const;
+    bool trigger(const QString &folderType, const QString &folderId, const QString &actionId) const;
+
+private:
+    QVariantList customItems(QObject *provider, const QString &folderId) const;
+    QHash<QString, QPointer<QObject>> m_providers;
+};
+
+}
diff --git a/tests/panels/dock/taskmanager/CMakeLists.txt b/tests/panels/dock/taskmanager/CMakeLists.txt
index 57a5bfbd0..2131b6770 100644
--- a/tests/panels/dock/taskmanager/CMakeLists.txt
+++ b/tests/panels/dock/taskmanager/CMakeLists.txt
@@ -49,3 +49,13 @@ target_include_directories(rolegroupmodel_tests PRIVATE
 )
 
 gtest_discover_tests(rolegroupmodel_tests)
+
+# Folder-source menu extensions are tested without a desktop or applet service.
+add_executable(foldermenuregistry_tests
+    foldermenuregistrytests.cpp
+    ${CMAKE_SOURCE_DIR}/panels/dock/taskmanager/foldermenuregistry.cpp
+    ${CMAKE_SOURCE_DIR}/panels/dock/taskmanager/foldermenuregistry.h
+)
+target_include_directories(foldermenuregistry_tests PRIVATE ${CMAKE_SOURCE_DIR}/panels/dock/taskmanager)
+target_link_libraries(foldermenuregistry_tests PRIVATE Qt${QT_VERSION_MAJOR}::Core Qt${QT_VERSION_MAJOR}::Test)
+add_test(NAME folder_menu_registry COMMAND foldermenuregistry_tests)
diff --git a/tests/panels/dock/taskmanager/foldermenuregistrytests.cpp b/tests/panels/dock/taskmanager/foldermenuregistrytests.cpp
new file mode 100644
index 000000000..e2260dc4b
--- /dev/null
+++ b/tests/panels/dock/taskmanager/foldermenuregistrytests.cpp
@@ -0,0 +1,133 @@
+// SPDX-FileCopyrightText: 2026 UnionTech Software Technology Co., Ltd.
+// SPDX-License-Identifier: GPL-3.0-or-later
+#include "foldermenuregistry.h"
+
+#include <QTest>
+#include <memory>
+
+class TestFolderMenuProvider : public QObject
+{
+    Q_OBJECT
+public:
+    QVariantList actions{QVariantMap{{"id", "details"}, {"name", "Details"}}};
+    QString requestedFolder;
+    QString triggeredFolder;
+    QString triggeredAction;
+    int triggerCount = 0;
+    Q_INVOKABLE QVariantList folderMenuActions(const QString &folderId)
+    {
+        requestedFolder = folderId;
+        return actions;
+    }
+    Q_INVOKABLE void triggerFolderMenuAction(const QString &folderId, const QString &actionId)
+    {
+        triggeredFolder = folderId;
+        triggeredAction = actionId;
+        ++triggerCount;
+    }
+};
+
+class FolderMenuRegistryTest : public QObject
+{
+    Q_OBJECT
+private slots:
+    void defaultMenuOnlyContainsNameAndUndock()
+    {
+        dock::FolderMenuRegistry registry;
+        const auto items = registry.menuItems("launcher", "internal/folders/12", "My folder");
+        QCOMPARE(items.size(), 2);
+        QCOMPARE(items[0].toMap().value("id").toString(), "open-folder");
+        QCOMPARE(items[0].toMap().value("name").toString(), "My folder");
+        QCOMPARE(items[1].toMap().value("id").toString(), "undock-folder");
+        QVERIFY(!registry.trigger("launcher", "internal/folders/12", "details"));
+    }
+    void customActionsAreAppendedAndDispatchedToTheirSource()
+    {
+        dock::FolderMenuRegistry registry;
+        TestFolderMenuProvider launcher, files;
+        QVERIFY(registry.registerProvider("launcher", &launcher));
+        QVERIFY(registry.registerProvider("files", &files));
+        const auto items = registry.menuItems("launcher", "internal/folders/12", "My folder");
+        QCOMPARE(items.size(), 3);
+        QCOMPARE(items[2].toMap().value("id").toString(), "details");
+        QCOMPARE(launcher.requestedFolder, "internal/folders/12");
+        QVERIFY(registry.trigger("launcher", "internal/folders/12", "details"));
+        QCOMPARE(launcher.triggeredFolder, "internal/folders/12");
+        QCOMPARE(launcher.triggeredAction, "details");
+        QCOMPARE(files.triggerCount, 0);
+        QCOMPARE(registry.menuItems("unregistered", "id", "Name").size(), 2);
+    }
+    void reservedDuplicateAndMalformedItemsCannotOverrideTheFramework()
+    {
+        dock::FolderMenuRegistry registry;
+        TestFolderMenuProvider provider;
+        provider.actions = {
+            QVariantMap{{"id", "open-folder"}, {"name", "Replace open"}},
+            QVariantMap{{"id", "undock-folder"}, {"name", "Replace undock"}},
+            QVariantMap{{"id", "details"}, {"name", "Details"}},
+            QVariantMap{{"id", "details"}, {"name", "Duplicate"}},
+            QVariantMap{{"id", ""}, {"name", "No identity"}},
+            QVariantMap{{"id", "unnamed"}},
+            QVariantMap{{"id", "hidden"}, {"name", "Hidden"}, {"visible", false}}
+        };
+        QVERIFY(registry.registerProvider("launcher", &provider));
+        QCOMPARE(registry.menuItems("launcher", "id", "Folder").size(), 3);
+        QVERIFY(!registry.trigger("launcher", "id", "open-folder"));
+        QVERIFY(!registry.trigger("launcher", "id", "undock-folder"));
+        QVERIFY(!registry.trigger("launcher", "id", "hidden"));
+        QVERIFY(!registry.trigger("launcher", "id", "unknown"));
+        QCOMPARE(provider.triggerCount, 0);
+    }
+    void enabledAndCheckedStateIsProvidedByPlugin()
+    {
+        dock::FolderMenuRegistry registry;
+        TestFolderMenuProvider provider;
+        provider.actions = {QVariantMap{{"id", "details"}, {"name", "Details"},
+                                       {"enabled", false}, {"checkable", true}, {"checked", true}}};
+        QVERIFY(registry.registerProvider("launcher", &provider));
+        const auto custom = registry.menuItems("launcher", "id", "Folder")[2].toMap();
+        QCOMPARE(custom.value("enabled").toBool(), false);
+        QCOMPARE(custom.value("checkable").toBool(), true);
+        QCOMPARE(custom.value("checked").toBool(), true);
+        QVERIFY(!registry.trigger("launcher", "id", "details"));
+        provider.actions = {QVariantMap{{"id", "details"}, {"name", "Details"}}};
+        QVERIFY(registry.trigger("launcher", "id", "details"));
+        // Actions can change while a native menu is open.
+        provider.actions.clear();
+        QVERIFY(!registry.trigger("launcher", "id", "details"));
+        QCOMPARE(provider.triggerCount, 1);
+    }
+    void registrationIsOwnedByItsPlugin()
+    {
+        dock::FolderMenuRegistry registry;
+        TestFolderMenuProvider first, other;
+        QObject invalid;
+        QVERIFY(!registry.registerProvider("", &first));
+        QVERIFY(!registry.registerProvider("launcher", nullptr));
+        QVERIFY(!registry.registerProvider("launcher", &invalid));
+        QVERIFY(registry.registerProvider("launcher", &first));
+        QVERIFY(registry.registerProvider("launcher", &first));
+        QVERIFY(!registry.registerProvider("launcher", &other));
+        registry.unregisterProvider("launcher", &other);
+        QCOMPARE(registry.menuItems("launcher", "id", "Folder").size(), 3);
+        registry.unregisterProvider("launcher", &first);
+        QCOMPARE(registry.menuItems("launcher", "id", "Folder").size(), 2);
+        QVERIFY(!registry.trigger("launcher", "id", "details"));
+        QVERIFY(registry.registerProvider("launcher", &other));
+    }
+    void destroyingProviderRestoresTheDefaultMenu()
+    {
+        dock::FolderMenuRegistry registry;
+        auto provider = std::make_unique<TestFolderMenuProvider>();
+        QVERIFY(registry.registerProvider("launcher", provider.get()));
+        provider.reset();
+        QCOMPARE(registry.menuItems("launcher", "id", "Folder").size(), 2);
+        QVERIFY(!registry.trigger("launcher", "id", "details"));
+        TestFolderMenuProvider replacement;
+        QVERIFY(registry.registerProvider("launcher", &replacement));
+        QCOMPARE(registry.menuItems("launcher", "id", "Folder").size(), 3);
+    }
+};
+
+QTEST_GUILESS_MAIN(FolderMenuRegistryTest)
+#include "foldermenuregistrytests.moc"