A direct-played file's own subtitle stream (WebKit lists an mp4's mov_text) was switched to hidden and drawn under any choice, Off included: only the player's <track> is kept hidden and read, other subtitle tracks are switched off. The lift was measured in screen pixels and applied inside the x1.25 windowed player, and re-measured off a box carrying its own (or a mid-slide) transform: an untransformed outer box is measured, the distance divided by the scale, and a cue that just appeared is placed, not slid from where the last one was left.