Position panel relative to screen by changing 'level' attribute (#274)
Position panel relative to screen by changing 'level' attribute (#274)

This change ensures the panel doesn't move when the parent browser
window moves.

This change also sets the z-index so that the min-vid panel is shown
above all Firefox windows, and (on Mac) the panel is shown even if FF
loses application focus.

Fixes #253.
meandavejustice/min-vid,meandavejustice/min-vid,meandavejustice/min-vid