diff --git a/src/gui/BufferPane.cc b/src/gui/BufferPane.cc
index 7ce9a92..1998625 100644
--- a/src/gui/BufferPane.cc
+++ b/src/gui/BufferPane.cc
@@ -226,7 +226,7 @@ int BufferPane::draw_buffer_line(int screen_row, const Buffer::Iterator & start_
                 bool wrap = (code_point == '\t');
                 int row = draw_row;
                 int col = screen_column;
-                int w = insert_mode() ? 1 : character_width;
+                int w = insert_mode() ? 1 : std::max(1, character_width);
                 while (w--)
                 {
                     draw_cursor(col_x(col), row_y(row));