diff --git a/Doc/tools/static/copybutton.js b/Doc/tools/static/copybutton.js
index dbd1de5..716c9e4 100644
--- a/Doc/tools/static/copybutton.js
+++ b/Doc/tools/static/copybutton.js
@@ -28,6 +28,7 @@
             var button = $('<span class="copybutton">&gt;&gt;&gt;</span>');
             button.css(button_styles)
             button.attr('title', hide_text);
+            button.data('hidden', 'false');
             jthis.prepend(button);
         }
         // tracebacks (.gt) contain bare text elements that need to be