diff --git a/src/bin/dosh-client.rs b/src/bin/dosh-client.rs
index f3079bb..dcc58ed 100644
--- a/src/bin/dosh-client.rs
+++ b/src/bin/dosh-client.rs
@@ -5774,6 +5774,7 @@ fn stale_mouse_report_len(bytes: &[u8], offset: usize) -> Option<usize> {
         },
         byte if byte.is_ascii_digit() => mouse_report_params_len(bytes, offset, 1)
             .or_else(|| orphan_mouse_suffix_len(bytes, offset)),
+        b'M' | b'm' if offset == 0 => orphan_leading_mouse_terminator_len(bytes, offset),
         _ => None,
     }
 }
@@ -5810,6 +5811,13 @@ fn orphan_mouse_suffix_len(bytes: &[u8], offset: usize) -> Option<usize> {
     None
 }
 
+fn orphan_leading_mouse_terminator_len(bytes: &[u8], offset: usize) -> Option<usize> {
+    if offset != 0 || !matches!(bytes.get(offset), Some(b'M' | b'm')) {
+        return None;
+    }
+    mouse_report_params_len(bytes, offset + 1, 1).map(|len| len + 1)
+}
+
 fn stale_mouse_report_maybe_incomplete(bytes: &[u8], offset: usize) -> bool {
     let Some(rest) = bytes.get(offset..) else {
         return false;
@@ -8907,11 +8915,18 @@ mod tests {
         assert_eq!(strip_stale_mouse_reports(b"10m"), b"");
     }
 
+    #[test]
+    fn leading_mouse_terminator_from_split_report_is_stripped() {
+        assert_eq!(strip_stale_mouse_reports(b"M35;149;1Mls\r"), b"ls\r");
+        assert_eq!(strip_stale_mouse_reports(b"m35;149;1Mls\r"), b"ls\r");
+    }
+
     #[test]
     fn numeric_semicolon_input_survives_stale_filter() {
         assert_eq!(strip_stale_mouse_reports(b"123;"), b"123;");
         assert_eq!(strip_stale_mouse_reports(b"12;34"), b"12;34");
         assert_eq!(strip_stale_mouse_reports(b"echo 1;"), b"echo 1;");
+        assert_eq!(strip_stale_mouse_reports(b"make test"), b"make test");
     }
 
     #[test]