diff --git a/demo/client.ts b/demo/client.ts
index fa98ee4e..7a601898 100644
--- a/demo/client.ts
+++ b/demo/client.ts
@@ -172,7 +172,7 @@ function runFakeTerminal(): void {
       term.prompt();
     } else if (ev.keyCode === 8) {
      // Do not delete the prompt
-      if (term.x > 2) {
+      if (term._core.buffer.x > 2) {
         term.write('\b \b');
       }
     } else if (printable) {