We need a possibility to force the Linux Drive client to "Sync NOW!"
due to the fact that the client by itself does NOT sync changes immediately
but in only checks the server once per huge random amount of time (in the range of many hours to days).
The client always claims to be fully synced which it is quite obviously not. Even after a forced restart of the client.
The files were added from another client (Mac) and are visible in the Web interface, so they were definitely uploaded.