selection: push data to compositor on acquire for Wayland (select→paste)

WINGs/selection_x11.c

@@ -353,6 +353,26 @@ Bool WMCreateSelectionHandler(WMView * view, WMNativeAtom selection, Time timest
 
 	WMAddToArray(selHandlers, handler);
 
+	/* On Wayland (no X11 SelectionRequest events), immediately push
+	 * the selection data via the clipboard store path so external
+	 * clients can paste it.  The data is fetched from the view's
+	 * convertSelection callback. */
+	if (vb->selection_fetch && handler->procs.convertSelection) {
+		WMNativeAtom textAtom = XA_STRING;
+		WMNativeAtom type;
+		WMData *data = handler->procs.convertSelection(handler->view,
+				selection, textAtom, handler->data, &type);
+		if (data) {
+			if (view->screen->viewBackend->clipboard_store) {
+				view->screen->viewBackend->clipboard_store(
+					view->screen->viewBackendCtx,
+					WMDataBytes(data),
+					WMGetDataLength(data));
+			}
+			WMReleaseData(data);
+		}
+	}
+
 	return True;
 }