diff --git a/src/history.rs b/src/history.rs
index 540cb5e..e8da053 100644
--- a/src/history.rs
+++ b/src/history.rs
@@ -525,6 +525,97 @@ mod tests {
                     "",
                 ][..],
             ),
+            // Multi-byte characters
+            (
+                &[
+                    "🐶🐱",
+                    "🐮🐰",
+                    "🐧🐭",
+                ][..],
+                (0, 0),
+                &[
+                    "🐷", "🐼", "🐴",
+                ][..],
+                &[
+                    "🐷",
+                    "🐼",
+                    "🐴🐶🐱",
+                    "🐮🐰",
+                    "🐧🐭",
+                ][..],
+            ),
+            (
+                &[
+                    "🐶🐱",
+                    "🐮🐰",
+                    "🐧🐭",
+                ][..],
+                (0, 4 * 2),
+                &[
+                    "🐷", "🐼", "🐴",
+                ][..],
+                &[
+                    "🐶🐱🐷",
+                    "🐼",
+                    "🐴",
+                    "🐮🐰",
+                    "🐧🐭",
+                ][..],
+            ),
+            (
+                &[
+                    "🐶🐱",
+                    "🐮🐰",
+                    "🐧🐭",
+                ][..],
+                (1, 0),
+                &[
+                    "🐷", "🐼", "🐴",
+                ][..],
+                &[
+                    "🐶🐱",
+                    "🐷",
+                    "🐼",
+                    "🐴🐮🐰",
+                    "🐧🐭",
+                ][..],
+            ),
+            (
+                &[
+                    "🐶🐱",
+                    "🐮🐰",
+                    "🐧🐭",
+                ][..],
+                (1, 4 * 1),
+                &[
+                    "🐷", "🐼", "🐴",
+                ][..],
+                &[
+                    "🐶🐱",
+                    "🐮🐷",
+                    "🐼",
+                    "🐴🐰",
+                    "🐧🐭",
+                ][..],
+            ),
+            (
+                &[
+                    "🐶🐱",
+                    "🐮🐰",
+                    "🐧🐭",
+                ][..],
+                (2, 4 * 2),
+                &[
+                    "🐷", "🐼", "🐴",
+                ][..],
+                &[
+                    "🐶🐱",
+                    "🐮🐰",
+                    "🐧🐭🐷",
+                    "🐼",
+                    "🐴",
+                ][..],
+            ),
         ];
 
         for (before, pos, input, expected) in tests {
diff --git a/tests/textarea.rs b/tests/textarea.rs
index 4847b36..6354af4 100644
--- a/tests/textarea.rs
+++ b/tests/textarea.rs
@@ -375,6 +375,92 @@ fn test_insert_str_multiple_lines() {
                 "",
             ][..],
         ),
+        // Multi-byte characters
+        (
+            &[
+                "🐶🐱",
+                "🐮🐰",
+                "🐧🐭",
+            ][..],
+            (0, 0),
+            "🐷\n🐼\n🐴",
+            (2, 1),
+            &[
+                "🐷",
+                "🐼",
+                "🐴🐶🐱",
+                "🐮🐰",
+                "🐧🐭",
+            ][..],
+        ),
+        (
+            &[
+                "🐶🐱",
+                "🐮🐰",
+                "🐧🐭",
+            ][..],
+            (0, 2),
+            "🐷\n🐼\n🐴",
+            (2, 1),
+            &[
+                "🐶🐱🐷",
+                "🐼",
+                "🐴",
+                "🐮🐰",
+                "🐧🐭",
+            ][..],
+        ),
+        (
+            &[
+                "🐶🐱",
+                "🐮🐰",
+                "🐧🐭",
+            ][..],
+            (1, 0),
+            "🐷\n🐼\n🐴",
+            (3, 1),
+            &[
+                "🐶🐱",
+                "🐷",
+                "🐼",
+                "🐴🐮🐰",
+                "🐧🐭",
+            ][..],
+        ),
+        (
+            &[
+                "🐶🐱",
+                "🐮🐰",
+                "🐧🐭",
+            ][..],
+            (1, 1),
+            "🐷\n🐼\n🐴",
+            (3, 1),
+            &[
+                "🐶🐱",
+                "🐮🐷",
+                "🐼",
+                "🐴🐰",
+                "🐧🐭",
+            ][..],
+        ),
+        (
+            &[
+                "🐶🐱",
+                "🐮🐰",
+                "🐧🐭",
+            ][..],
+            (2, 2),
+            "🐷\n🐼\n🐴",
+            (4, 1),
+            &[
+                "🐶🐱",
+                "🐮🐰",
+                "🐧🐭🐷",
+                "🐼",
+                "🐴",
+            ][..],
+        ),
     ];
 
     for test in tests {