jQuery: Uncaught TypeError: url.indexOf is not a function

I got the “url.indexOf and e.indexOf is not a function” errors on my website. I got this error after my upgrade to my Magento webshop, but this error can happen on any website with a jQuery version upgrade.

Error:

Uncaught TypeError: e.indexOf is not a function
    at w.fn.load (jquery-3.3.1.min.js:2:82468)
    at caribbean-montego-mntgo-shell:1483:19
    at Object.execCb (require.js:1696:33)
    at Module.check (require.js:883:51)
    at Module.<anonymous> (require.js:1139:34)
    at require.js:134:23
    at require.js:1189:21
    at each (require.js:59:31)
    at Module.emit (require.js:1188:17)
    at Module.check (require.js:938:30)

Uncaught TypeError: url.indexOf is not a function
    at jQuery.fn.load (jquery.js:10363:23)
    at (index):1166:19
    at Object.execCb (require.js:1696:33)
    at Module.check (require.js:883:51)
    at Module.<anonymous> (require.js:1139:34)
    at require.js:134:23
    at require.js:1189:21
    at each (require.js:59:31)
    at Module.emit (require.js:1188:17)
    at Module.check (require.js:938:30)

Cause:

Here’s the jQuery version 3 release note: https://blog.jquery.com/2016/06/09/jquery-3-0-final-released/

Removed deprecated event aliases (https://github.com/jquery/jquery/issues/2286)

– .load, .unload, and .error, deprecated since jQuery 1.8, are no more.
– Use .on() to register listeners.

Solution:

Search your custom/third-party modules code and replace the following deprecated excerpt:

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

with the following:

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

Hope this helps. Thanks.