Hi Alexsandar
I have just rechecked the site hte ticker is no longer working if logged in our out of the site. I also tried on mobile phone. In relation to your questions please see below info:
1) We don't use cloud flare or any caching plugins
2) I have been trying in firefox and chrome and edge on my mobile
3) I am not an expert on the console however i could see any obvious errors related to JavaScript
4) code section on page
<div class="fusion-column fusion-one-third last spacing-yes margin-home"/>
<?php echo do_shortcode('[stock_ticker symbols="^IXIC" show="" zero=“#2bb431" minus="#df0024" plus="#2bb431" static="" nolink=""]'); ?>
</div>
cheers Paul