Index: ps/trunk/binaries/data/mods/_test.gui/gui/regainFocus/page_emptyPage.xml
===================================================================
--- ps/trunk/binaries/data/mods/_test.gui/gui/regainFocus/page_emptyPage.xml
+++ ps/trunk/binaries/data/mods/_test.gui/gui/regainFocus/page_emptyPage.xml
@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<page>
+	<include>common/styles.xml</include>
+</page>
Index: ps/trunk/binaries/data/mods/_test.gui/gui/regainFocus/page_pushWithPopOnInit.xml
===================================================================
--- ps/trunk/binaries/data/mods/_test.gui/gui/regainFocus/page_pushWithPopOnInit.xml
+++ ps/trunk/binaries/data/mods/_test.gui/gui/regainFocus/page_pushWithPopOnInit.xml
@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<page>
+	<include>common/styles.xml</include>
+	<include>regainFocus/pushWithPopOnInit.xml</include>
+</page>
Index: ps/trunk/binaries/data/mods/_test.gui/gui/regainFocus/pushWithPopOnInit.js
===================================================================
--- ps/trunk/binaries/data/mods/_test.gui/gui/regainFocus/pushWithPopOnInit.js
+++ ps/trunk/binaries/data/mods/_test.gui/gui/regainFocus/pushWithPopOnInit.js
@@ -0,0 +1 @@
+Engine.PushGuiPage("regainFocus/page_emptyPage.xml", {}, () => Engine.PopGuiPage());
Index: ps/trunk/binaries/data/mods/_test.gui/gui/regainFocus/pushWithPopOnInit.xml
===================================================================
--- ps/trunk/binaries/data/mods/_test.gui/gui/regainFocus/pushWithPopOnInit.xml
+++ ps/trunk/binaries/data/mods/_test.gui/gui/regainFocus/pushWithPopOnInit.xml
@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<objects>
+	<script file="gui/regainFocus/pushWithPopOnInit.js"/>
+</objects>
Index: ps/trunk/source/gui/GUIManager.h
===================================================================
--- ps/trunk/source/gui/GUIManager.h
+++ ps/trunk/source/gui/GUIManager.h
@@ -24,6 +24,7 @@
 #include "ps/TemplateLoader.h"
 #include "scriptinterface/StructuredClone.h"
 
+#include <deque>
 #include <string>
 #include <unordered_set>
 
@@ -167,7 +168,12 @@
 	std::shared_ptr<ScriptContext> m_ScriptContext;
 	std::shared_ptr<ScriptInterface> m_ScriptInterface;
 
-	using PageStackType = std::vector<SGUIPage>;
+	/**
+	 * The page stack must not move pointers on push/pop, or pushing a page in a page's init method
+	 * may crash (as the pusher page will suddenly have moved, and the stack will be confused).
+	 * Therefore use std::deque over std::vector.
+	 */
+	using PageStackType = std::deque<SGUIPage>;
 	PageStackType m_PageStack;
 
 	CTemplateLoader m_TemplateLoader;
Index: ps/trunk/source/gui/tests/test_GuiManager.h
===================================================================
--- ps/trunk/source/gui/tests/test_GuiManager.h
+++ ps/trunk/source/gui/tests/test_GuiManager.h
@@ -197,4 +197,29 @@
 
 		UnloadHotkeys();
 	}
+
+	void test_PageRegainedFocusEvent()
+	{
+		// Load up a test page.
+		const ScriptInterface& scriptInterface = *(g_GUI->GetScriptInterface());
+		ScriptRequest rq(scriptInterface);
+		JS::RootedValue val(rq.cx);
+		Script::CreateObject(rq, &val);
+
+		Script::StructuredClone data = Script::WriteStructuredClone(rq, JS::NullHandleValue);
+		g_GUI->PushPage(L"regainFocus/page_emptyPage.xml", data, JS::UndefinedHandleValue);
+
+		const ScriptInterface& pageScriptInterface = *(g_GUI->GetActiveGUI()->GetScriptInterface());
+		ScriptRequest prq(pageScriptInterface);
+		JS::RootedValue global(prq.cx, prq.globalValue());
+
+		g_GUI->PushPage(L"regainFocus/page_emptyPage.xml", data, JS::UndefinedHandleValue);
+		g_GUI->PopPage(data);
+
+		// This page instantly pushes an empty page with a callback that pops another page again.
+		g_GUI->PushPage(L"regainFocus/page_pushWithPopOnInit.xml", data, JS::UndefinedHandleValue);
+
+		// Pop the empty page and trigger the callback (effectively pops twice).
+		g_GUI->PopPage(data);
+	}
 };