@Philipp & @mashborn I have updated my productive system to the latest snapshot as well and had similar effects.
One major issue was that I had the HTTP binding on many items with requests that timed out. This cause the event handling to be black-listed and thus no events being processed anymore.
I don’t really know why the blacklisting happens now, if one binding isn’t returning quickly (which all of them are supposed to do, so we are actually talking about bugs in the bindings that now pop up) - I assume that something must have changed in Felix EventAdmin or Apache Karaf. I cannot rule out that it is due to some change in ESH (e.g. the new communication handling with profiles), though, but it is all a bit mysterious to me really…
@sjka is working on https://github.com/eclipse/smarthome/pull/4602, which should make sure that a single mis-behaving binding cannot impact the whole system anymore - we should have this in place next week.
Until then you can try to figure out what binding might cause the problem. I have removed the HTTP stuff in my case, which solved most of the problem for me. I still had a situation where no commands were processed after a start, but on a restart, everything was up normal again.
Hope this helps a bit for the moment!
Kai