I searched for "show_button" and found no related posts, so here goes. I frequently get the following error when working with my project, using Firebug in Firefox:

show_button is not defined prototype.js(line 273)

and the following error content:

show_button is not defined evalScripts("\n show_button('extra_data_text', 'text version')\n ")prototype.js (line 272) collect("\n show_button('extra_data_text', 'text version')\n ", 5)prototype.js (line 486) (no name)("\n show_button('extra_data_text', 'text version')\n ")prototype.js (line 450) _each(function())prototype.js (line 675) each(function())prototype.js (line 449) collect(function())prototype.js (line 485) evalScripts()prototype.js (line 272) (no name)()prototype.js (line 1358) [Break on this error] },

Is this a bug in prototype, or something else that just appears like one?