This Bugzilla instance is a read-only archive of historic NetBeans bug reports. To report a bug in NetBeans please follow the project's instructions for reporting issues.
This is just reminder to think about this usecase: (See issue 31772 for more details.) The xml/core module creates TopComponent and serialize it. The created settings file is bound to xml/core module. So far so good. The problem is that this TopComponent is CloneableEditor and serializing CloneableEditor will serialize also CloneableOpenSupport and its Env. But Env in case of xml/core TopComponent is from different module - it is from xml/tree. And if xml/tree is disabled and xml/core is enabled the settings infrastructure will try to deserialize this settings what will result in ClassNotFound exception.
Reassigning to new module owner jskrivanek.
As I understand from issue 31772, it is handled in window system.