diff --git a/activation.cpp b/activation.cpp
index 9e5dac3ba6..fc93bbdd0a 100644
--- a/activation.cpp
+++ b/activation.cpp
@@ -722,7 +722,7 @@ xcb_timestamp_t Client::readUserTimeMapTimestamp(const KStartupInfoId *asn_id, c
         // Otherwise, refuse activation of a window
         // from already running application if this application
         // is not the active one (unless focus stealing prevention is turned off).
-        Client* act = workspace()->mostRecentlyActivatedClient();
+        Client* act = dynamic_cast<Client*>(workspace()->mostRecentlyActivatedClient());
         if (act != NULL && !belongToSameApplication(act, this, true)) {
             bool first_window = true;
             auto sameApplicationActiveHackPredicate = [this](const Client *cl) {
diff --git a/events.cpp b/events.cpp
index f79d48066f..2cd292d810 100644
--- a/events.cpp
+++ b/events.cpp
@@ -491,7 +491,7 @@ bool Workspace::workspaceEvent(xcb_generic_event_t *e)
             updateXTime(); // focusToNull() uses xTime(), which is old now (FocusIn has no timestamp)
             if (!currentInput.isNull() && (currentInput->focus == XCB_WINDOW_NONE || currentInput->focus == XCB_INPUT_FOCUS_POINTER_ROOT)) {
                 //kWarning( 1212 ) << "X focus set to None/PointerRoot, reseting focus" ;
-                Client *c = mostRecentlyActivatedClient();
+                AbstractClient *c = mostRecentlyActivatedClient();
                 if (c != NULL)
                     requestFocus(c, true);
                 else if (activateNextClient(NULL))
diff --git a/group.cpp b/group.cpp
index 2e9f0edba0..f0c9e1533e 100644
--- a/group.cpp
+++ b/group.cpp
@@ -1052,7 +1052,7 @@ void Client::checkActiveModal()
     // if the active window got new modal transient, activate it.
     // cannot be done in AddTransient(), because there may temporarily
     // exist loops, breaking findModal
-    Client* check_modal = workspace()->mostRecentlyActivatedClient();
+    Client* check_modal = dynamic_cast<Client*>(workspace()->mostRecentlyActivatedClient());
     if (check_modal != NULL && check_modal->check_active_modal) {
         Client* new_modal = dynamic_cast<Client*>(check_modal->findModal());
         if (new_modal != NULL && new_modal != check_modal) {
diff --git a/layers.cpp b/layers.cpp
index a273e8d6ab..32dc02c309 100644
--- a/layers.cpp
+++ b/layers.cpp
@@ -880,7 +880,7 @@ bool Client::isActiveFullScreen() const
     if (!isFullScreen())
         return false;
 
-    const Client* ac = workspace()->mostRecentlyActivatedClient(); // instead of activeClient() - avoids flicker
+    const Client* ac = dynamic_cast<Client*>(workspace()->mostRecentlyActivatedClient()); // instead of activeClient() - avoids flicker
     // according to NETWM spec implementation notes suggests
     // "focused windows having state _NET_WM_STATE_FULLSCREEN" to be on the highest layer.
     // we'll also take the screen into account
diff --git a/workspace.cpp b/workspace.cpp
index 0aecf8f05e..3e8b25500f 100644
--- a/workspace.cpp
+++ b/workspace.cpp
@@ -1671,6 +1671,11 @@ AbstractClient *Workspace::activeClient() const
     return active_client;
 }
 
+AbstractClient *Workspace::mostRecentlyActivatedClient() const
+{
+    return should_get_focus.count() > 0 ? should_get_focus.last() : active_client;
+}
+
 } // namespace
 
 #include "workspace.moc"
diff --git a/workspace.h b/workspace.h
index 8df61112d7..76612e856f 100644
--- a/workspace.h
+++ b/workspace.h
@@ -144,7 +144,7 @@ public:
      * we didn't process yet the matching FocusIn event. Used mostly in focus
      * stealing prevention code.
      */
-    Client* mostRecentlyActivatedClient() const;
+    AbstractClient* mostRecentlyActivatedClient() const;
 
     Client* clientUnderMouse(int screen) const;
 
@@ -634,11 +634,6 @@ inline bool Workspace::initializing() const
     return workspaceInit;
 }
 
-inline Client* Workspace::mostRecentlyActivatedClient() const
-{
-    return should_get_focus.count() > 0 ? should_get_focus.last() : active_client;
-}
-
 inline void Workspace::addGroup(Group* group)
 {
     emit groupAdded(group);