youtube fullscreen prematuraly ending

[arminius]

not quite sure how to sum up this problem for the subject.
I have a dual display, 1 is a computer moniter, the other is an LCD TV connecte via HDMI.
I have youtube videos over on my LCD TV, and I have them set to fullscreen.
Problem is that the second I click on anything in my moniters screen, it cancels fullscreen on my LCD TV.

Can anything be done to prevent this?