This may be caused by several things, e.g. broken IPv6 in your network or some
incompatible SW you have installed (e.g. Cisco AnyConnect Web Security Module),
but without any useful info, it is hard to say more.

Well, maybe looking into the system log, before starting blindly restarting your machine
would not be a bad idea…

We do, of course, test our software, before we release it. But it is not possible to test it in
all environments, that may occur on several hundred thousands of machines.