I recently upgraded my staging website from Joomla 5 to Joomla 6. Since the upgrade, the SP Page Builder frontend editor/preview will not load when using the Fixter template. It displays the loading spinner indefinitely.
Environment:
Joomla: 6.1.3
SP Page Builder: 6.8.0
Fixter: 2.0.3
Helix Ultimate Framework: 2.2.10
PHP: 8.3.24
Staging URL: https://nebdri.cloudaccess.host/
Testing already completed:
SP Page Builder backend editor works normally.
Existing pages display normally on the public frontend.
Created a completely blank SP Page Builder test page — frontend editor still spins.
Switched the default template from Fixter to Cassiopeia — SP Page Builder frontend editor works normally.
Switched back to Fixter — frontend editor spins again.
Browser console does not show a fatal JavaScript error.
SPPB AJAX/XHR requests return HTTP 200.
The edit_iframe request returns HTTP 200.
Tested private/incognito browser session.
Cleared Joomla and browser cache.
JavaScript compression is OFF.
CSS compression is OFF.
Tested Compile SCSS to CSS OFF.
Tested SP Page Builder “Hide Editor Modules” ON.
No custom JavaScript is entered in Fixter Custom Code.
No /templates/shaper_fixter/html/com_sppagebuilder/ override exists.
No /templates/shaper_fixter/sppagebuilder/ addon override directory exists.
/templates/shaper_fixter/overrides/ contains only index.html.
Behaviour – Backward Compatibility was tested both enabled and disabled with no difference.
I also downloaded the current Fixter 2.0.3 template package and attempted to reinstall it. Joomla displayed this installer warning:
JInstaller::Install: File does not exist [ROOT][TMP]/.../template/en-GB.tpl_fixter.ini
The public site also appears to load more slowly with Fixter than expected.
Because the SP Page Builder frontend editor works immediately when Cassiopeia is the default template, this appears to be specific to Fixter/Helix after the Joomla 6 upgrade.
Could you please investigate whether there is a Fixter 2.0.3 compatibility/file issue causing the SP Page Builder 6.8.0 frontend editor iframe to fail to initialize under Joomla 6.1.3?