diff --git a/aegisub/src/ass_attachment.cpp b/aegisub/src/ass_attachment.cpp
index 10d8684ef..8a0820ed0 100644
--- a/aegisub/src/ass_attachment.cpp
+++ b/aegisub/src/ass_attachment.cpp
@@ -79,12 +79,13 @@ AssAttachment::~AssAttachment() {
 /// @brief Clone 
 /// @return 
 ///
-AssEntry *AssAttachment::Clone() {
+AssEntry *AssAttachment::Clone() const {
 	// New object
 	AssAttachment *clone = new AssAttachment(filename);
 
 	// Copy fields
 	clone->data = data;
+	clone->group = group;
 
 	// Return
 	return clone;
diff --git a/aegisub/src/ass_attachment.h b/aegisub/src/ass_attachment.h
index c9411fa3b..cc3109139 100644
--- a/aegisub/src/ass_attachment.h
+++ b/aegisub/src/ass_attachment.h
@@ -96,7 +96,7 @@ public:
 	/// @brief DOCME
 	///
 	ASS_EntryType GetType() { return ENTRY_ATTACHMENT; }
-	AssEntry *Clone();
+	AssEntry *Clone() const;
 
 	AssAttachment(wxString name);
 	~AssAttachment();