script.js:20 Uncaught TypeError: card_title.indexOf is not a function code example

Example: e.indexOf is not a function at k.fn.init.k.fn.load

This error might be caused by the jQuery event-aliases like .load(),
.unload() or .error() that all are deprecated since jQuery 1.8. Lookup 
for these aliases in your code and replace them with the .on() method
instead. For example, replace the following deprecated excerpt:

$(window).load(function(){...});

with the following:

$(window).on('load', function(){ ...});