diff --git a/desktop/api.cpp b/desktop/api.cpp
index 5ae2a96..2f5a6d6 100644
--- a/desktop/api.cpp
+++ b/desktop/api.cpp
@@ -61,6 +61,7 @@ struct EnumString { const char *cName; int value; };
 #define DESKTOP_MSG_SYSTEM_CONFIGURATION_GET  (13)
 #define DESKTOP_MSG_FILE_TYPES_GET            (14)
 #define DESKTOP_MSG_UNHANDLED_KEY_EVENT       (15)
+#define DESKTOP_MSG_START_USER_TASK           (16)
 
 struct EsFileStore {
 #define FILE_STORE_HANDLE        (1)
@@ -1550,6 +1551,7 @@ const void *EsEmbeddedFileGet(const char *_name, ptrdiff_t nameBytes, size_t *by
 struct UserTask {
 	EsUserTaskCallbackFunction callback;
 	EsGeneric data;
+	EsHandle taskHandle;
 };
 
 void UserTaskThread(EsGeneric _task) {
@@ -1558,23 +1560,48 @@ void UserTaskThread(EsGeneric _task) {
 	EsMessageMutexAcquire();
 	api.openInstanceCount--; 
 	// TODO Send ES_MSG_APPLICATION_EXIT if needed.
-	// TODO Tell Desktop the task is complete.
 	EsMessageMutexRelease();
+	EsSyscall(ES_SYSCALL_WINDOW_CLOSE, task->taskHandle, 0, 0, 0);
+	EsHandleClose(task->taskHandle);
 	EsHeapFree(task);
 }
 
 EsError EsUserTaskStart(EsUserTaskCallbackFunction callback, EsGeneric data) {
 	EsMessageMutexCheck();
+
 	UserTask *task = (UserTask *) EsHeapAllocate(sizeof(UserTask), true);
-	if (!task) return ES_ERROR_INSUFFICIENT_RESOURCES;
+
+	if (!task) {
+		return ES_ERROR_INSUFFICIENT_RESOURCES;
+	}
+
+	uint8_t m = DESKTOP_MSG_START_USER_TASK;
+	EsBuffer response = { .canGrow = true };
+	MessageDesktop(&m, 1, ES_INVALID_HANDLE, &response);
+	EsHandle handle;
+	EsBufferReadInto(&response, &handle, sizeof(handle));
+	EsHeapFree(response.out);
+
+	if (!handle) {
+		EsHeapFree(task);
+		return ES_ERROR_INSUFFICIENT_RESOURCES;
+	}
+
 	task->callback = callback;
 	task->data = data;
-	// TODO Tell Desktop about the task. (This'll also prevent it sending ES_MSG_APPLICATION_EXIT in single process mode.)
-	api.openInstanceCount++;
+	task->taskHandle = handle;
 	EsThreadInformation information;
 	EsError error = EsThreadCreate(UserTaskThread, &information, task);
-	if (error == ES_SUCCESS) EsHandleClose(information.handle);
-	else EsHeapFree(task);
+
+	if (error == ES_SUCCESS) {
+		EsHandleClose(information.handle);
+		api.openInstanceCount++;
+	} else {
+		EsSyscall(ES_SYSCALL_WINDOW_CLOSE, task->taskHandle, 0, 0, 0);
+		EsHandleClose(task->taskHandle);
+		EsHeapFree(task);
+	}
+
 	return error;
 }
 
diff --git a/desktop/desktop.cpp b/desktop/desktop.cpp
index 245f55a..fe7732f 100644
--- a/desktop/desktop.cpp
+++ b/desktop/desktop.cpp
@@ -137,7 +137,7 @@ struct BlankTabInstance : CommonDesktopInstance {
 
 struct ApplicationInstance {
 	// User interface.
-	WindowTab *tab; // nullptr for notRespondingInstance.
+	WindowTab *tab; // nullptr for notRespondingInstance and user tasks.
 	EsObjectID embeddedWindowID;
 	EsHandle embeddedWindowHandle;
 
@@ -145,8 +145,9 @@ struct ApplicationInstance {
 	InstalledApplication *application;
 	EsObjectID documentID, processID;
 	EsHandle processHandle;
+	bool isUserTask;
 
-	// Tab information.
+	// Metadata.
 	char title[128];
 	size_t titleBytes;
 	uint32_t iconID;
@@ -182,6 +183,7 @@ struct {
 
 	TaskBar taskBar;
 	EsWindow *wallpaperWindow;
+	EsButton *tasksButton;
 
 	bool shutdownWindowOpen;
 	bool setupDesktopUIComplete;
@@ -729,12 +731,12 @@ int TaskBarMessage(EsElement *element, EsMessage *message) {
 	return 0;
 }
 
-int TaskBarTasksButtonMessage(EsElement *element, EsMessage *message) {
+int TaskBarTasksButtonMessage(EsElement *, EsMessage *message) {
 	if (message->type == ES_MSG_GET_WIDTH) {
 		message->measure.width = GetConstantNumber("taskBarTasksButtonWidth");
 		return ES_HANDLED;
 	} else if (message->type == ES_MSG_PAINT_ICON) {
-		float progress = 0.33f;
+		float progress = 0.0f; // TODO.
 
 		uint32_t color1 = GetConstantNumber("taskBarTasksButtonWheelColor1");
 		uint32_t color2 = GetConstantNumber("taskBarTasksButtonWheelColor2");
@@ -1200,8 +1202,10 @@ void ApplicationInstanceCrashed(EsMessage *message) {
 		ApplicationInstance *instance = desktop.allApplicationInstances[i];
 
 		if (instance->processID == message->crash.pid) {
-			ApplicationInstanceStart(APPLICATION_ID_DESKTOP_CRASHED, nullptr, instance);
-			WindowTabActivate(instance->tab, true);
+			if (instance->tab) {
+				ApplicationInstanceStart(APPLICATION_ID_DESKTOP_CRASHED, nullptr, instance);
+				WindowTabActivate(instance->tab, true);
+			}
 		}
 	}
 
@@ -1884,8 +1888,8 @@ void DesktopSetup() {
 			desktop.taskBar.taskList.Initialise(panel, ES_CELL_FILL, ReorderListMessage, nullptr);
 			desktop.taskBar.taskList.cName = "task list";
 
-			EsButton *tasksButton = EsButtonCreate(panel, ES_ELEMENT_HIDDEN, ES_STYLE_TASK_BAR_BUTTON, "Copying files" ELLIPSIS, -1);
-			tasksButton->messageUser = TaskBarTasksButtonMessage;
+			desktop.tasksButton = EsButtonCreate(panel, ES_ELEMENT_HIDDEN, ES_STYLE_TASK_BAR_BUTTON, "Copying files" ELLIPSIS, -1);
+			desktop.tasksButton->messageUser = TaskBarTasksButtonMessage;
 
 			EsButton *shutdownButton = EsButtonCreate(panel, ES_FLAGS_DEFAULT, ES_STYLE_TASK_BAR_EXTRA);
 			EsButtonSetIcon(shutdownButton, ES_ICON_SYSTEM_SHUTDOWN_SYMBOLIC);
@@ -1953,7 +1957,7 @@ void DesktopSetup() {
 	desktop.setupDesktopUIComplete = true;
 }
 
-void DesktopMessage2(EsMessage *message, uint8_t *buffer, EsBuffer *pipe) {
+void DesktopSyscall(EsMessage *message, uint8_t *buffer, EsBuffer *pipe) {
 	ApplicationInstance *instance = ApplicationInstanceFindByWindowID(message->desktop.windowID);
 
 	if (buffer[0] == DESKTOP_MSG_START_APPLICATION) {
@@ -2045,6 +2049,57 @@ void DesktopMessage2(EsMessage *message, uint8_t *buffer, EsBuffer *pipe) {
 		if (application && (application->permissions & APPLICATION_PERMISSION_ALL_FILES)) {
 			InstanceAnnouncePathMoved(application, buffer, message->desktop.bytes);
 		}
+	} else if (buffer[0] == DESKTOP_MSG_START_USER_TASK && pipe) {
+		InstalledApplication *application = ApplicationFindByPID(message->desktop.processID);
+
+		if (!application) {
+			return;
+		}
+
+		// HACK User tasks use an embedded window object for IPC.
+		// 	This allows us to basically treat them like other instances.
+
+		EsHandle processHandle = EsProcessOpen(message->desktop.processID);
+		EsHandle windowHandle = EsSyscall(ES_SYSCALL_WINDOW_CREATE, ES_WINDOW_NORMAL, 0, 0, 0);
+		ApplicationInstance *instance = (ApplicationInstance *) EsHeapAllocate(sizeof(ApplicationInstance), true);
+		bool added = false;
+
+		if (processHandle && windowHandle && instance) {
+			added = desktop.allApplicationInstances.Add(instance);
+		}
+
+		if (!processHandle || !windowHandle || !instance || !added) {
+			if (processHandle) EsHandleClose(processHandle);
+			if (windowHandle) EsHandleClose(windowHandle);
+			if (instance) EsHeapFree(instance);
+
+			EsHandle invalid = ES_INVALID_HANDLE;
+			EsBufferWrite(pipe, &invalid, sizeof(invalid));
+			return;
+		}
+
+		instance->title[0] = ' ';
+		instance->titleBytes = 1;
+		instance->isUserTask = true;
+		instance->embeddedWindowHandle = windowHandle;
+		instance->embeddedWindowID = EsSyscall(ES_SYSCALL_WINDOW_GET_ID, windowHandle, 0, 0, 0);
+		instance->processHandle = processHandle;
+		instance->processID = message->desktop.processID;
+		instance->application = application;
+
+		if (application->singleProcessHandle) {
+			EsAssert(application->openInstanceCount);
+			application->openInstanceCount++;
+		}
+
+		EsHandle targetWindowHandle = EsSyscall(ES_SYSCALL_WINDOW_SET_PROPERTY, windowHandle, processHandle, 0, ES_WINDOW_PROPERTY_EMBED_OWNER);
+		EsBufferWrite(pipe, &targetWindowHandle, sizeof(targetWindowHandle));
+
+		if (EsElementIsHidden(desktop.tasksButton)) {
+			EsPanelStartMovementAnimation((EsPanel *) EsElementGetLayoutParent(desktop.tasksButton), 1.5f /* duration scale */);
+			EsElementStartTransition(desktop.tasksButton, ES_TRANSITION_FADE_IN, ES_ELEMENT_TRANSITION_ENTRANCE, 1.5f);
+			EsElementSetHidden(desktop.tasksButton, false);
+		}
 	} else if (!instance) {
 		// -------------------------------------------------
 		// | Messages below here require a valid instance. |
@@ -2059,10 +2114,12 @@ void DesktopMessage2(EsMessage *message, uint8_t *buffer, EsBuffer *pipe) {
 			}
 		}
 
-		instance->tab->Repaint(true);
+		if (instance->tab) {
+			instance->tab->Repaint(true);
 
-		if (instance->tab == instance->tab->container->active) {
-			instance->tab->container->taskBarButton->Repaint(true);
+			if (instance->tab == instance->tab->container->active) {
+				instance->tab->container->taskBarButton->Repaint(true);
+			}
 		}
 	} else if (buffer[0] == DESKTOP_MSG_REQUEST_SAVE) {
 		ApplicationInstanceRequestSave(instance, (const char *) buffer + 1, message->desktop.bytes - 1);
@@ -2201,7 +2258,7 @@ void DesktopMessage(EsMessage *message) {
 		if (buffer) {
 			EsConstantBufferRead(message->desktop.buffer, buffer);
 			EsBuffer pipe = { .canGrow = true };
-			DesktopMessage2(message, buffer, &pipe);
+			DesktopSyscall(message, buffer, &pipe);
 			if (message->desktop.pipe) EsPipeWrite(message->desktop.pipe, pipe.out, pipe.position);
 			EsHeapFree(pipe.out);
 			EsHeapFree(buffer);
diff --git a/desktop/gui.cpp b/desktop/gui.cpp
index 84f2929..abf3a52 100644
--- a/desktop/gui.cpp
+++ b/desktop/gui.cpp
@@ -321,6 +321,7 @@ struct ScrollPane {
 struct PanelMovementItem {
 	EsElement *element;
 	EsRectangle oldBounds;
+	bool wasHidden;
 };
 
 struct EsPanel : EsElement {
@@ -1903,15 +1904,19 @@ void PanelMoveChild(EsElement *element, int width, int height, int offsetX, int
 			continue;
 		}
 
-		int oldWidth = Width(item->oldBounds);
-		int oldHeight = Height(item->oldBounds);
-		int oldOffsetX = item->oldBounds.l;
-		int oldOffsetY = item->oldBounds.t;
+		if (item->wasHidden) {
+			break;
+		} else {
+			int oldWidth = Width(item->oldBounds);
+			int oldHeight = Height(item->oldBounds);
+			int oldOffsetX = item->oldBounds.l;
+			int oldOffsetY = item->oldBounds.t;
 
-		element->InternalMove(LinearInterpolate(oldWidth, width, progress),
-				LinearInterpolate(oldHeight, height, progress),
-				LinearInterpolate(oldOffsetX, offsetX, progress),
-				LinearInterpolate(oldOffsetY, offsetY, progress));
+			element->InternalMove(LinearInterpolate(oldWidth, width, progress),
+					LinearInterpolate(oldHeight, height, progress),
+					LinearInterpolate(oldOffsetX, offsetX, progress),
+					LinearInterpolate(oldOffsetY, offsetY, progress));
+		}
 
 		return;
 	}
@@ -3471,6 +3476,7 @@ void EsPanelStartMovementAnimation(EsPanel *panel, float timeMultiplier) {
 		item.element = element;
 		item.oldBounds = ES_RECT_4(element->offsetX, element->offsetX + element->width, 
 				element->offsetY, element->offsetY + element->height);
+		item.wasHidden = element->flags & ES_ELEMENT_HIDDEN;
 		panel->movementItems.Add(item);
 	}
 
@@ -5643,6 +5649,11 @@ void EsElementSetHidden(EsElement *element, bool hidden) {
 	UIMaybeRemoveFocusedElement(element->window);
 }
 
+bool EsElementIsHidden(EsElement *element) {
+	EsMessageMutexCheck();
+	return element->flags & ES_ELEMENT_HIDDEN;
+}
+
 void EsElementSetDisabled(EsElement *element, bool disabled) {
 	EsMessageMutexCheck();
 
diff --git a/desktop/os.header b/desktop/os.header
index 6f6666e..0291102 100644
--- a/desktop/os.header
+++ b/desktop/os.header
@@ -2285,6 +2285,7 @@ function void EsElementFocus(EsElement *element, uint32_t flags = ES_FLAGS_DEFAU
 function bool EsElementIsFocused(EsElement *element);
 function void EsElementSetDisabled(EsElement *element, bool disabled = true);
 function void EsElementSetHidden(EsElement *element, bool hidden = true);
+function bool EsElementIsHidden(EsElement *element);
 function void EsElementSetCallback(EsElement *element, EsUICallbackFunction callback);
 function void EsElementGetSize(EsElement *element, int *width, int *height);
 function void EsElementRepaint(EsElement *element, const EsRectangle *region = ES_NULL); // Mark an element to be repainted. If region is null, then the whole element is repainted.
diff --git a/desktop/syscall.cpp b/desktop/syscall.cpp
index 97194e7..1cd2e10 100644
--- a/desktop/syscall.cpp
+++ b/desktop/syscall.cpp
@@ -717,7 +717,7 @@ size_t EsGameControllerStatePoll(EsGameControllerState *buffer) {
 	return EsSyscall(ES_SYSCALL_GAME_CONTROLLER_STATE_POLL, (uintptr_t) buffer, 0, 0, 0);
 }
 
-void DesktopMessage2(EsMessage *message, uint8_t *buffer, EsBuffer *pipe);
+void DesktopSyscall(EsMessage *message, uint8_t *buffer, EsBuffer *pipe);
 
 void MessageDesktop(void *message, size_t messageBytes, EsHandle embeddedWindow = ES_INVALID_HANDLE, EsBuffer *responseBuffer = nullptr) {
 	if (api.startupInformation->isDesktop) {
@@ -726,7 +726,7 @@ void MessageDesktop(void *message, size_t messageBytes, EsHandle embeddedWindow
 		m.desktop.windowID = embeddedWindow ? EsSyscall(ES_SYSCALL_WINDOW_GET_ID, embeddedWindow, 0, 0, 0) : 0;
 		m.desktop.processID = EsProcessGetID(ES_CURRENT_PROCESS);
 		m.desktop.bytes = messageBytes;
-		DesktopMessage2(&m, (uint8_t *) message, responseBuffer);
+		DesktopSyscall(&m, (uint8_t *) message, responseBuffer);
 	} else {
 		EsHandle pipeRead = ES_INVALID_HANDLE, pipeWrite = ES_INVALID_HANDLE;
 
diff --git a/util/api_table.ini b/util/api_table.ini
index 993029d..bb2f8b8 100644
--- a/util/api_table.ini
+++ b/util/api_table.ini
@@ -433,3 +433,4 @@ EsFileCopy=431
 EsListViewSelectNone=432
 EsElementIsFocused=433
 EsUserTaskStart=434
+EsElementIsHidden=435