Slider height and/or width are not valid or smaller than 50px

Do you have images smaller than 50px?
Link to your site?

No images or a normal slider on the page…

https://monoliting-arhitekti.com/energetska-izkaznica/

and

https://monoliting-arhitekti.com/oblikovanje/

You have a widget in the left sidebar:

<aside class="widget widget_weptile-image-slider-widget" id="weptile-image-slider-widget-2"><p>Slider height and/or width are not valid or smaller than 50px</p></aside>

So it’s about that plug-in not about customizr ??

That did the trick! Thank you.