Hi,
I decided to migrate the existing site from Joomla 4 to Joomla 5 and caused the following error in the Administrator Panel:
0 Class "JPlugin" not found
I enabled debug and see this one:
![Image]()
This result I get when I proceed to System > Global Configuration or System > Extensions.
The content plugin causes this issue on the backend?
There are the following extensions installed on the site:
![Image]()
It seems the plugins (content and other) need to be adapted to work on Joomla 5 even with Backwards Compatibility plugin.
Thanks.
UPD: I thought Backwards Compatibility plugin was enabled after the update, but it did not. By enabling it the problem could be resolved. However, it is better to adapt PD's plugins someday.
I decided to migrate the existing site from Joomla 4 to Joomla 5 and caused the following error in the Administrator Panel:
0 Class "JPlugin" not found
I enabled debug and see this one:

This result I get when I proceed to System > Global Configuration or System > Extensions.
The content plugin causes this issue on the backend?
There are the following extensions installed on the site:

It seems the plugins (content and other) need to be adapted to work on Joomla 5 even with Backwards Compatibility plugin.
Thanks.
UPD: I thought Backwards Compatibility plugin was enabled after the update, but it did not. By enabling it the problem could be resolved. However, it is better to adapt PD's plugins someday.
Statistics: Posted by sulpher — 20 Feb 2025, 09:06