I am using the new version 18.104.22.168 of the host and viewer.
I like using the full screen view for my remote sessions. I noticed that the taskbar when set to auto hide will completely disappear when you attempt to use it after the loss of connection. On reboots of the host I like to either close or minimize the remote screen, but when the screen turns to black and white or solid black the taskbar disappears when you move the mouse to it. I am then stuck in the remote screen until it reconnects or times out. This did not happen in the 6.3 version.
I can pin the taskbar so it stays visible at all times, but it is nice to have it auto hide.