https://github.com/fcitx/fcitx/issues/241
https://github.com/fcitx/fcitx/commit/c737618fffa84bfe5a6caf55cee9b9288a791bbf
https://github.com/fcitx/fcitx/commit/353683e29be4ef26409b9a05e0cb647a5180fa8c
https://github.com/fcitx/fcitx/commit/fe2732db27a1c2e183400ceeb3283559e10a4ca8
https://github.com/fcitx/fcitx/commit/440c431d29876a8e4871159d289bc9a573f9a41b

--- /src/module/notificationitem/notificationitem.c
+++ /src/module/notificationitem/notificationitem.c
@@ -565,8 +565,17 @@
 
 boolean FcitxNotificationItemEnable(FcitxNotificationItem* notificationitem, FcitxNotificationItemAvailableCallback callback, void* data)
 {
-    if (!callback || notificationitem->callback)
+    if (!callback)
         return false;
+
+    if (notificationitem->callback == callback) {
+        return true;
+    }
+
+    if (notificationitem->callback) {
+        return false;
+    }
+
     if (notificationitem->serviceName) {
         FcitxLog(ERROR, "This should not happen, please report bug.");
         return false;
--- /src/ui/classic/TrayWindow.c
+++ /src/ui/classic/TrayWindow.c
@@ -48,7 +48,7 @@
     Display *dpy = classicui->dpy;
     int iScreen = classicui->iScreen;
     char   strWindowName[] = "Fcitx Tray Window";
-    if (!classicui->bUseTrayIcon || classicui->isSuspend)
+    if (!classicui->bUseTrayIcon || classicui->isSuspend || classicui->notificationItemAvailable)
         return;
 
     if (trayWindow->window == None && trayWindow->dockWindow != None) {
@@ -61,12 +61,12 @@
             wsa.colormap = colormap;
             wsa.background_pixel = 0;
             wsa.border_pixel = 0;
-            trayWindow->window = XCreateWindow(dpy, p, -1, -1, 1, 1,
+            trayWindow->window = XCreateWindow(dpy, p, -1, -1, 22, 22,
                                             0, vi->depth, InputOutput, vi->visual,
                                             CWBackPixmap | CWBackPixel | CWBorderPixel | CWColormap, &wsa);
         } else {
             trayWindow->window = XCreateSimpleWindow(dpy, DefaultRootWindow(dpy),
-                                -1, -1, 1, 1, 0,
+                                -1, -1, 22, 22, 0,
                                 BlackPixel(dpy, DefaultScreen(dpy)),
                                 WhitePixel(dpy, DefaultScreen(dpy)));
             XSetWindowBackgroundPixmap(dpy, trayWindow->window, ParentRelative);
@@ -74,6 +74,7 @@
         if (trayWindow->window == (Window) NULL)
             return;
 
+        trayWindow->size = 22;
         XSizeHints size_hints;
         size_hints.flags = PWinGravity | PBaseSize;
         size_hints.base_width = trayWindow->size;
@@ -161,7 +162,7 @@
     png_surface = image->image;
 
     c = cairo_create(trayWindow->cs);
-    cairo_set_source_rgba(c, 0, 0, 0, 0);
+    cairo_set_source_rgba(c, 1, 1, 1, 0);
     cairo_set_operator(c, CAIRO_OPERATOR_SOURCE);
     cairo_paint(c);
 
@@ -226,8 +227,6 @@
         if (event->xclient.message_type == trayWindow->atoms[ATOM_MANAGER]
             && event->xclient.data.l[1] == trayWindow->atoms[ATOM_SELECTION]
             && trayWindow->dockWindow == None) {
-            if (classicui->notificationItemAvailable)
-                return true;
             trayWindow->dockWindow = event->xclient.data.l[2];
             TrayWindowRelease(trayWindow);
             TrayWindowInit(trayWindow);
@@ -245,6 +244,7 @@
             int size = event->xconfigure.height;
             if (size != trayWindow->size) {
                 trayWindow->size = size;
+                XResizeWindow(dpy, trayWindow->window, size, size);
                 XSizeHints size_hints;
                 size_hints.flags = PWinGravity | PBaseSize;
                 size_hints.base_width = trayWindow->size;
@@ -286,6 +286,14 @@
             return true;
         }
         break;
+    case PropertyNotify:
+        if (event->xproperty.atom == trayWindow->atoms[ATOM_VISUAL] &&
+            event->xproperty.window == trayWindow->dockWindow) {
+            TrayWindowRelease(trayWindow);
+            TrayWindowInit(trayWindow);
+            return true;
+        }
+        break;
     }
     return false;
 }
--- /src/ui/classic/classicui.c
+++ /src/ui/classic/classicui.c
@@ -168,7 +168,7 @@
 void ClassicUIDelayedInitTray(void* arg) {
     FcitxClassicUI* classicui = (FcitxClassicUI*) arg;
     // FcitxLog(INFO, "yeah we delayed!");
-    if (!classicui->bUseTrayIcon)
+    if (!classicui->bUseTrayIcon || classicui->isSuspend)
         return;
     /*
      * if this return false, something wrong happened and callback
@@ -187,7 +187,7 @@
 {
     FcitxClassicUI* classicui = (FcitxClassicUI*) arg;
     classicui->trayTimeout = 0;
-    if (!classicui->bUseTrayIcon)
+    if (!classicui->bUseTrayIcon || classicui->isSuspend)
         return;
 
     if (!classicui->trayWindow->bTrayMapped) {
--- /src/ui/classic/tray.c
+++ /src/ui/classic/tray.c
@@ -106,8 +106,9 @@
 
     XWindowAttributes attr;
     XGetWindowAttributes(dpy, DefaultRootWindow(dpy), &attr);
-    if ((attr.your_event_mask & StructureNotifyMask) != StructureNotifyMask) {
-        XSelectInput(dpy, DefaultRootWindow(dpy), attr.your_event_mask | StructureNotifyMask); // for MANAGER selection
+    int neededMask = StructureNotifyMask;
+    if ((attr.your_event_mask & neededMask) != neededMask) {
+        XSelectInput(dpy, DefaultRootWindow(dpy), attr.your_event_mask | neededMask); // for MANAGER selection
     }
     return True;
 }
@@ -123,7 +124,7 @@
     Display* dpy = tray->owner->dpy;
 
     if (tray->dockWindow != None) {
-        XSelectInput(dpy, tray->dockWindow, StructureNotifyMask);
+        XSelectInput(dpy, tray->dockWindow, PropertyChangeMask | StructureNotifyMask);
         TraySendOpcode(tray, SYSTEM_TRAY_REQUEST_DOCK, tray->window, 0, 0);
         tray->bTrayMapped = True;
         return 1;