diff --git a/src/gui/BufferPane.cc b/src/gui/BufferPane.cc
index 207af91..9747b89 100644
--- a/src/gui/BufferPane.cc
+++ b/src/gui/BufferPane.cc
@@ -236,6 +236,9 @@ int BufferPane::draw_buffer_line(int screen_row, const Buffer::Iterator & start_
                 {
                     if (code_point < 0x20u)
                     {
+                        m_window->gl()->draw_rect(win_x(x + 2), win_y(y),
+                                m_window->font()->get_advance() * 2 - 4, 1,
+                                0, 0.7, 1.0, 1.0);
                         m_window->gl()->draw_character(win_x(x), win_y(y), '^', *m_window->font(), 1.0, 1.0, 1.0, 1.0);
                         m_window->gl()->draw_character(win_x(col_x(screen_column + 1)), win_y(y), code_point | 0x40u, *m_window->font(), 1.0, 1.0, 1.0, 1.0);
                     }