I found that Syncthing site and its services is blocking IP addresses from 126.96.36.199 to 188.8.131.52
Is it true?
We have installed Syncthing on three computers.
Synchronization works when all of three computers is in one local network.
When one of computers connects over Internet, synchronization is not working.
When we try to change our ISP (Yota Tver), synchronization works again.
Service of Yota affirm that they is not blocking Syncthing.
Site http://syncthing.net from that IP's is not available too.
Pings performs correctly.
It seems like Syncthing blocks queries from IP addresses from 184.108.40.206 to 220.127.116.11