diff --git a/src/core/utf8.c b/src/core/utf8.c
index cdb272f5..9faaac89 100644
--- a/src/core/utf8.c
+++ b/src/core/utf8.c
@@ -399,6 +399,20 @@ int unichar_array_find_cluster_start(const unichar *text, int text_len, int pos)
 #endif
 }
 
+int is_combining_char(unichar c)
+{
+	if (!is_utf8())
+		return 0;
+
+#ifdef HAVE_LIBUTF8PROC
+	/* Use utf8proc for precise combining character detection */
+	return unichar_isprint(c) && utf8proc_charwidth(c) == 0;
+#else
+	/* Fallback to unichar_width for compatibility */
+	return unichar_isprint(c) && unichar_width(c) == 0;
+#endif
+}
+
 void utf8_init(void)
 {
 	/* no-op */
diff --git a/src/core/utf8.h b/src/core/utf8.h
index 2893f58d..694e1bdf 100644
--- a/src/core/utf8.h
+++ b/src/core/utf8.h
@@ -72,6 +72,10 @@ int unichar_array_move_cluster_backward(const unichar *text, int text_len, int *
  * Returns the codepoint index of the cluster start. */
 int unichar_array_find_cluster_start(const unichar *text, int text_len, int pos);
 
+/* Check if a unichar is a combining character (width 0).
+ * Returns 1 if the character is combining, 0 otherwise. */
+int is_combining_char(unichar c);
+
 /* Initialize UTF-8 debugging system */
 void utf8_init(void);
 
diff --git a/src/fe-text/gui-entry.c b/src/fe-text/gui-entry.c
index 69c5d942..243ec49f 100644
--- a/src/fe-text/gui-entry.c
+++ b/src/fe-text/gui-entry.c
@@ -54,20 +54,6 @@ static unichar i_tolower(unichar c)
 	return c <= 255 ? tolower(c) : c;
 }
 
-static int is_combining_char(unichar c)
-{
-	if (term_type != TERM_TYPE_UTF8)
-		return 0;
-
-#ifdef HAVE_LIBUTF8PROC
-	/* Use utf8proc for precise combining character detection */
-	return unichar_isprint(c) && utf8proc_charwidth(c) == 0;
-#else
-	/* Fallback to unichar_width for compatibility */
-	return unichar_isprint(c) && unichar_width(c) == 0;
-#endif
-}
-
 static int i_isalnum(unichar c)
 {
 	if (term_type == TERM_TYPE_UTF8)