Didn't want to start a new thread - I think, this needs to be updated.
First of all, there is no good or even necessary reason for not beeing able to hide the taskbar or rather no reason for not having it disappear when watching full screen video. It's just a design flaw. And it is a flaw.
Because, secondly, your understanding (and also the PR of Avast and hopefully not the developers) of the security feature that Safe Zone is about seems to be very odd to me (myself being an IT-Expert for quite some years now). You shouldn't use (exclusively) Safe Zone for banking and shopping etc., but use it for sites that are likely to try to infect your system, instead of taking that huge risk of using your normal browser for those sites. That way you can browse even dangerously infectious territory and still maintain a safe system - for using banking either with the normal browser or Safe Zone. The other way around seems absurd, because one shouldn't trust a compromised system even when using Safe Zone on it.
But either way my first point stands and needs to be adressed soon, as it shouldn't take too much effort to enable a possibility to hide the taskbar (with full screen video).