Staggs not workinf

I am trying to debug a strange issue on a WordPress site and would really appreciate some help.

I have a configurator page here:

https://tridentmodular.com.ua/configurator/garden/ Problem

The page looks different depending on whether the visitor is logged in or not:

• Logged-in users / admin: the configurator appears normal
• Logged-out users / incognito: the layout is broken, and the page shows a WordPress-style “critical error” message near the bottom

So this is not just a small CSS difference — the public version seems to break structurally. What I checked already Browser checks

I opened DevTools in incognito:

• Console showed no obvious JS errors
• Network did not show anything clearly suspicious at first
• I may still need to inspect more carefully with cache fully disabled

WordPress debug log

I enabled WP_DEBUG and checked the log.

The lines I found were mainly:

• Complianz notices about translations being loaded too early
• one warning from Kadence Blocks Pro:
  foreach() argument must be of type array|object, string given

However, I am not sure that warning belongs to this configurator page specifically, because the log is global and this configurator itself does not directly use Kadence. What makes this confusing

• The problem happens only for logged-out users
• Logged-in admins see the page working
• I am not yet sure whether this is caused by:
  • cache/optimization for guests
  • AJAX not working for non-logged-in visitors
  • a PHP fatal in the configurator code
  • PDF/email functionality near the bottom of the page
  • some global template/plugin conflict

Extra clue

The issue seems to happen around the area where the page renders the bottom controls such as:

• Send Email
• Download to PDF

So I suspect that section may be related. My question

What would you check first in a case where:

1. a WordPress front-end page works for logged-in users
2. breaks for logged-out users
3. looks like a server-side/PHP issue rather than a pure CSS issue

And specifically:

• could this be a missing wp_ajax_nopriv_* handler?
• could cache/optimization create this exact logged-in vs logged-out difference?
• what is the best way to isolate the exact fatal error for only this page request?

If helpful, I can also share:

• screenshots of the two layouts
• the relevant configurator code
• debug log excerpts
• plugin stack

Thanks a lot.

The page I need help with: [log in to see the link]