Hello,
I have a new, up-to-date Joomla installation.
I installed the SP Cookie Consent plugin there.
After I activated this, Joomla stopped working.
The following error message came up:
0 Call to undefined method Joomla\CMS\Application\AdministratorApplication::isAdmin()
Nothing worked in the backend as well as in the frontend.
After I deactivated the plug-in directly in the database via phpMyAdmin, Joomla works again.
You have released this plug-in for Joomla 4.
You should take this back as soon as possible and check and revise the plug-in again.
It is simply fatal when masses of Joomla installations are paralyzed with such a plug-in.
Thank You!
greeting
sven