3 files changed, 9 insertions, 0 deletions
diff --git a/Userland/Libraries/LibGUI/TextDocument.cpp b/Userland/Libraries/LibGUI/TextDocument.cpp
index 6799e5c90d..27042d1696 100644
--- a/Userland/Libraries/LibGUI/TextDocument.cpp
+++ b/Userland/Libraries/LibGUI/TextDocument.cpp
@@ -41,6 +41,7 @@ TextDocument::~TextDocument()
 bool TextDocument::set_text(const StringView& text)
 {
     m_client_notifications_enabled = false;
+    m_undo_stack.clear();
     m_spans.clear();
     remove_all_lines();
 
diff --git a/Userland/Libraries/LibGUI/UndoStack.cpp b/Userland/Libraries/LibGUI/UndoStack.cpp
index 7267c83bf4..7f32d3e4fb 100644
--- a/Userland/Libraries/LibGUI/UndoStack.cpp
+++ b/Userland/Libraries/LibGUI/UndoStack.cpp
@@ -80,4 +80,10 @@ void UndoStack::finalize_current_combo()
     m_stack.prepend(move(undo_commands_container));
 }
 
+void UndoStack::clear()
+{
+    m_stack.clear();
+    m_stack_index = 0;
+}
+
 }
diff --git a/Userland/Libraries/LibGUI/UndoStack.h b/Userland/Libraries/LibGUI/UndoStack.h
index 0921d835a5..f854171c83 100644
--- a/Userland/Libraries/LibGUI/UndoStack.h
+++ b/Userland/Libraries/LibGUI/UndoStack.h
@@ -26,6 +26,8 @@ public:
 
     void finalize_current_combo();
 
+    void clear();
+
 private:
     struct UndoCommandsContainer {
         NonnullOwnPtrVector<Command> m_undo_vector;