Using Linux as both host and guest. Normal operation is fine. If you lock the client desktop (or the screensaver with a password activates) then you can no longer see the screen or send input. You just get a black window on the host. Sending commands via the web portal still work. Only way I've found to get connected is send a reboot command. That is not ideal as other work may be open on the client side.
OS is xUbuntu 16.04 & 16.10 (64-bit). Have not tried with other environments.
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