If any files had to be transmitted during initialization (because the files were not present on the client side), the synchronization on the shared files won't work. This seems to be a session-internal defect as the synchronization does work if IntelliJ is restarted after the transmission and a new session (which does not require the transfer of files) is established.
The synchronization might work during the inital session for files that were already present on both sides or might get fixed by simply ending end re-establishing the session (without restarting IntelliJ). I haven't come around to doing more detailed tests.
Do you mean the synchonization of the editors or the synchronization of the files ?
The files are transmitted correctly, but working on them does not work. Actions take in the editor are not transmitted.
Solved by the reimplementation of the filesystem handling.