@arminunruh new update:
the hosting provider told me this:

I verified that the server can't reach the address for the api call kernl.us
The limitation is not due to our server, is due to kernl.us server that refuse calls from our server.
We suggest to ask to the server developer so he could unlock your website to receive updates.

Any thoughts?
Is really this connection issue the cause of the wp-admin slowness?

Thank you very much.
Jacopo

@arminunruh just to add more details here...
Yestreday I installed the "Query monitor" plugin, and it analysed the abnormal wp-admin page loading time (usually between 25 and 40 seconds as you can see)...

Watching the stats, the plugin detected that there were some HTTP Api calls which needed a massive amount of time to be loaded...

It seems that the theme spends a lot of time trying to search new updates every time I load a new page, but something block it... Maybe there's something strange in it?
It could be the source of the problem?
This reminds me a thing... when I installed the theme for the first time, on thursday, it was the 5.2.0 version, and despite it was outdated there wasn't any update notification available...
Now the theme is updated but only because I uploaded manually an updated version of the theme.

Please let me know if this could be useful or if you discovered something new.
Thank you very much.
Jacopo

@arminunruh hi, thank you!
I sent everything you need to the mail you told me.

Waiting for news.
Thanks,
Jacopo

Hi there, I'm experiencing a big problem while I'm working on a website of a client.

My client purchased the "lay theme pro license", but since when I activated the theme on wordpress, the whole wordpress control panel started to be terribly slow.
Every change I do, every section I want to see, everything i try to do, it needs 30sec and more to load the page.
It's almost impossible to work in these conditions, very frustrating.

I already tried to deactivate plugins, reset database, data etc... nothing worked.

I even tried to clean completely the hosting space, then I recreated the database and reinstalled the cms, but nothing worked...
WP admin was was quick until the moment I activated lay theme, from that moment it returned to be slow.

How could I do?
The website is http://www.francescaocchi.com

Thanks in advance,
Regards,
Jacopo

Thank you @mariusjopen , i found the perfect solution for my problem, and it worked perfectly!

"When using jQuery, please use 'jQuery' instead of '$'"

Great, thanks for your suggestion & help.
Have a nice Easter.
Jacopo

Hi Armin, hi Marius.
I'm experimenting an issue with a thing I wanted to put into my website.

This is my problem: I'm trying to put this JS code in order to change a word randomly with a series of other words.
This is the code I put into the "head" section.

<script type="text/javascript">
// Array of words
var words = ['*', 'web' , 'graphic' , 'visual' , 'digital' , 'icon' , 'logo' , 'UI' , 'UX' , 'editorial' , 'infographic' , '(basic) illustration' , '(basic) video' , 'type' ];
// Function that executes every 2000 milliseconds
var t = setInterval(function() {
  // Random number generator
  var randomNumber = Math.round( Math.random() * (words.length-1) );
  // Change the word in the span for a random one in the array of words
  $('#changing').html( words[ randomNumber ] );
}, 2000);
</script>

Unfortunately, if I put only this code it doesnt' work,
So I tried to add this thing because I supposed the function needed Jquery:

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.4/jquery.min.js"></script>

And eventually the trick worked, but after that implementation I saw that the "scroll to top" feature doesn't work anymore.

So, what can I do if I want to keep both things full working but at the same time avoiding that kind of conflicts?

Thanks a lot.
Jacopo