Error in Inbox discovery

Hi,

since last update from Snapshot yesterday, I have no langer any Items in Inbox.
I get error 500 popping up when I enter and if I want to discovery new things in openhab.log i get following errors:
cannot notify the discoverylistener ‘org.eclipse.smarthome.config.discovery.internal.persistentinbox’ on all things removed event!

All old things and items are working.
Needed to change KNX config from 1.x to 2.3.0 snapshot.
I cleared cache an tmp folder, but it didn’t help.

debian OS, installed with apt-get

2018-03-27 21:18:35.393 [ERROR] [nternal.DiscoveryServiceRegistryImpl] - Cannot notify the DiscoveryListener ‘org.eclipse.smarthome.config.discovery.internal.PersistentInbox’ on all things removed event!
java.lang.NullPointerException: null
at org.eclipse.smarthome.config.discovery.internal.PersistentInbox.stream(PersistentInbox.java:293) ~[?:?]
at org.eclipse.smarthome.config.discovery.internal.PersistentInbox.getAll(PersistentInbox.java:288) ~[?:?]
at org.eclipse.smarthome.config.discovery.internal.PersistentInbox.removeOlderResults(PersistentInbox.java:336) ~[?:?]
at org.eclipse.smarthome.config.discovery.internal.DiscoveryServiceRegistryImpl$4.run(DiscoveryServiceRegistryImpl.java:357) ~[?:?]
at org.eclipse.smarthome.config.discovery.internal.DiscoveryServiceRegistryImpl$4.run(DiscoveryServiceRegistryImpl.java:1) ~[?:?]
at java.security.AccessController.doPrivileged(Native Method) ~[?:?]
at org.eclipse.smarthome.config.discovery.internal.DiscoveryServiceRegistryImpl.removeOlderResults(DiscoveryServiceRegistryImpl.java:354) ~[?:?]
at org.eclipse.smarthome.config.discovery.AbstractDiscoveryService.removeOlderResults(AbstractDiscoveryService.java:350) ~[?:?]
at org.eclipse.smarthome.config.discovery.AbstractDiscoveryService.removeOlderResults(AbstractDiscoveryService.java:315) ~[?:?]
at org.openhab.binding.homematic.internal.discovery.HomematicDeviceDiscoveryService.lambda$0(HomematicDeviceDiscoveryService.java:108) ~[?:?]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [?:?]
at java.util.concurrent.FutureTask.run(FutureTask.java:266) [?:?]
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180) [?:?]
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293) [?:?]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [?:?]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [?:?]
at java.lang.Thread.run(Thread.java:748) [?:?]