diff --git a/photo_tagger.py b/photo_tagger.py
index b4108e6..80a8be5 100644
--- a/photo_tagger.py
+++ b/photo_tagger.py
@@ -4613,6 +4613,46 @@ class PhotoTagger:
         save_button = ttk.Button(bottom_frame, text="Save Tagging")
         save_button.pack(side=tk.RIGHT, padx=10, pady=5)
         
+        # Quit button with warning for pending changes
+        def quit_with_warning():
+            """Quit the dialog, but warn if there are pending changes"""
+            # Check for pending changes
+            has_pending_changes = bool(pending_tag_changes or pending_tag_removals)
+            
+            if has_pending_changes:
+                total_additions = sum(len(tags) for tags in pending_tag_changes.values())
+                total_removals = sum(len(tags) for tags in pending_tag_removals.values())
+                
+                changes_text = []
+                if total_additions > 0:
+                    changes_text.append(f"{total_additions} tag addition(s)")
+                if total_removals > 0:
+                    changes_text.append(f"{total_removals} tag removal(s)")
+                
+                changes_summary = " and ".join(changes_text)
+                
+                result = messagebox.askyesnocancel(
+                    "Unsaved Changes", 
+                    f"You have unsaved changes: {changes_summary}.\n\n"
+                    "Do you want to save your changes before quitting?\n\n"
+                    "Yes = Save and quit\n"
+                    "No = Quit without saving\n"
+                    "Cancel = Stay in dialog"
+                )
+                
+                if result is True:  # Yes - Save and quit
+                    save_tagging_changes()
+                    root.destroy()
+                elif result is False:  # No - Quit without saving
+                    root.destroy()
+                # If result is None (Cancel), do nothing - stay in dialog
+            else:
+                # No pending changes, just quit
+                root.destroy()
+        
+        quit_button = ttk.Button(bottom_frame, text="Quit", command=quit_with_warning)
+        quit_button.pack(side=tk.RIGHT, padx=(0, 10), pady=5)
+        
         # Enable mouse scroll anywhere in the dialog
         def on_mousewheel(event):
             content_canvas.yview_scroll(int(-1*(event.delta/120)), "units")
@@ -5153,7 +5193,7 @@ class PhotoTagger:
                 # Top frame - dropdown to select tag to add
                 ttk.Label(top_frame, text="Add tag:").grid(row=0, column=0, padx=(0, 8), sticky=tk.W)
                 tag_var = tk.StringVar()
-                combo = ttk.Combobox(top_frame, textvariable=tag_var, values=available_tags, width=30)
+                combo = ttk.Combobox(top_frame, textvariable=tag_var, values=available_tags, width=30, state='readonly')
                 combo.grid(row=0, column=1, padx=(0, 8), sticky=(tk.W, tk.E))
                 combo.focus_set()