When I tried to delete a user in easysocial, I received an error. I could not delete users. The error was:
An error has occurred. 0 Class 'JString' not found
I am running a fresh joomla 4.0.3 installation with the latest easysocial.
I tried to search for a solution and found it on the joomla forum. It appears that that error is related to some easysocial plugins which are using JString, which is not available anymore in joomla 4. that is joomla 3 code... so not all easysocial plugins are joomla4 ready I suppose.
when I disabled the following plugins, I could delete users again in joomla:
Authentication - EasySocial
System - EasySocial
System - EasySocial AutoLogin
User - EasySocial
I am not sure, but I think those plugins are not joomla 4 ready yet...
the topic on the joomla forum can be found here:
https://forum.joomla.org/viewtopic.php?f=808&t=989007