diff --git a/shell/shellcorona.cpp b/shell/shellcorona.cpp
--- a/shell/shellcorona.cpp
+++ b/shell/shellcorona.cpp
@@ -1906,7 +1906,8 @@
 {
     Plasma::Containment *cont = nullptr;
     for (Plasma::Containment *c : m_desktopContainments.value(activity)) {
-        if (c->screen() == screenNum) {
+        //using lastScreen() instead of screen() catches also containments of other activities that aren't current, so not assigned to a screen right now
+        if (c->lastScreen() == screenNum) {
             cont = c;
             if (containment == cont) {
                 return;
@@ -1918,6 +1919,7 @@
     Q_ASSERT(!m_desktopContainments.value(activity).values().contains(containment));
 
     if (cont) {
+        m_desktopContainments[activity].remove(cont);
         disconnect(cont, SIGNAL(destroyed(QObject*)),
                 this, SLOT(desktopContainmentDestroyed(QObject*)));
         cont->destroy();