Hi,
Thanks for the clarification.
If it works correctly from the backend editor but fails only in the frontend editor, that strongly indicates the issue is still related to CDN / WAF security rules blocking frontend AJAX requests made by SP Page Builder.
In this case, please ask Hostinger support to bypass or whitelist the following frontend URLs and AJAX endpoints, not only the administrator area:
Paths to exclude from CDN / WAF:
/index.php?option=com_sppagebuilder*
/index.php?option=com_ajax*
/media/com_sppagebuilder/*
/components/com_sppagebuilder/*
The frontend editor uses AJAX POST requests from the public side, which are often blocked by aggressive firewall rules and result in 403 Forbidden errors.
Once these paths are excluded:
Frontend editor should work normally
Backend editor will remain unaffected
The site can stay secure with HTTPS enabled
After making these changes, please clear all caches (Joomla + CDN) and test again.
Best regards,