I changed the shortcut to switch between windowed
and fullscreen mode to F12 (hand injury makes the
default hard to enter). That is, in preferences,
I set windowed and fullscreen shortcut for the fullscreen
item to F12.
This seems to work great until I put my powerbook to
sleep. After waking again, COTVNC will reconnect the
session, but ignores F12 when I press it, sending the
keystroke thru to the remote host instead.
If I open preferences again, it shows that F12 is still
listed as the shortcut to switch fullscreen.
I can select it and set it to F12 again (which should be
no change), and this re-enables use of F12 as the
fullscreen shortcut. This is annoying, having to reset
it each time.
Exiting COTVNC and restarting it once it is in this
state does not resolve the problem. However, restarting
COTVNC otherwise leaves F12 functioning as I set it.