diff --git a/abstract_client.cpp b/abstract_client.cpp
--- a/abstract_client.cpp
+++ b/abstract_client.cpp
@@ -704,6 +704,7 @@
     };
     updateAppId();
     w->setSkipTaskbar(skipTaskbar());
+    w->setPid(pid());
     w->setShadeable(isShadeable());
     w->setShaded(isShade());
     w->setResizable(isResizable());
diff --git a/shell_client.h b/shell_client.h
--- a/shell_client.h
+++ b/shell_client.h
@@ -108,6 +108,15 @@
     quint32 windowId() const override {
         return m_windowId;
     }
+
+    /**
+     * The process for this client.
+     * Note that processes started by kwin will share its process id.
+     * @since 5.11
+     * @returns the process if for this client.
+     **/
+    pid_t pid() const override;
+
     bool isInternal() const;
     bool isLockScreen() const override;
     bool isInputMethod() const override;
diff --git a/shell_client.cpp b/shell_client.cpp
--- a/shell_client.cpp
+++ b/shell_client.cpp
@@ -981,6 +981,11 @@
                         m_internalWindow->geometry().size() + QSize(borderLeft() + borderRight(), borderTop() + borderBottom())));
 }
 
+pid_t ShellClient::pid() const
+{
+    return surface()->client()->processId();
+}
+
 bool ShellClient::isInternal() const
 {
     return m_internal;
diff --git a/toplevel.h b/toplevel.h
--- a/toplevel.h
+++ b/toplevel.h
@@ -289,7 +289,7 @@
     QByteArray wmClientMachine(bool use_localhost) const;
     const ClientMachine *clientMachine() const;
     Window wmClientLeader() const;
-    pid_t pid() const;
+    virtual pid_t pid() const;
     static bool resourceMatch(const Toplevel* c1, const Toplevel* c2);
 
     bool readyForPainting() const; // true if the window has been already painted its contents