x11/panelwindow: set _NET_WM_DESKTOP to stay on all desktops

src/x11/panel_window.cpp

@@ -185,7 +185,25 @@ void XPanelWindow::setFocusable(bool focusable) {
 	emit this->focusableChanged();
 }
 
-void XPanelWindow::xInit() { this->updateDimensions(); }
+void XPanelWindow::xInit() {
+	if (this->window == nullptr || this->window->handle() == nullptr) return;
+	this->updateDimensions();
+
+	auto* conn = x11Connection();
+
+	// Stick to every workspace
+	auto desktop = 0xffffffff;
+	xcb_change_property(
+			conn,
+			XCB_PROP_MODE_REPLACE,
+			this->window->winId(),
+			XAtom::_NET_WM_DESKTOP.atom(),
+			XCB_ATOM_CARDINAL,
+			32,
+			1,
+			&desktop
+	);
+}
 
 void XPanelWindow::connectScreen() {
 	if (this->mTrackedScreen != nullptr) {

src/x11/util.cpp

@@ -23,11 +23,13 @@ xcb_connection_t* x11Connection() {
 // NOLINTBEGIN
 XAtom XAtom::_NET_WM_STRUT {};
 XAtom XAtom::_NET_WM_STRUT_PARTIAL {};
+XAtom XAtom::_NET_WM_DESKTOP {};
 // NOLINTEND
 
 void XAtom::initAtoms() {
 	_NET_WM_STRUT.init("_NET_WM_STRUT");
 	_NET_WM_STRUT_PARTIAL.init("_NET_WM_STRUT_PARTIAL");
+	_NET_WM_DESKTOP.init("_NET_WM_DESKTOP");
 }
 
 void XAtom::init(const QByteArray& name) {

src/x11/util.hpp

@@ -15,6 +15,7 @@ public:
 	// NOLINTBEGIN
 	static XAtom _NET_WM_STRUT;
 	static XAtom _NET_WM_STRUT_PARTIAL;
+	static XAtom _NET_WM_DESKTOP;
 	// NOLINTEND
 
 	static void initAtoms();