If no visual effect is used (as in my screenshot) Totem should automatically
use the given space and Totem should not display this useless placeholder. A placeholder can be used ... but if there is a horizontal scrollbar the placeholder should disappear and this space should be used by the playlist.
If no sidebar is used you could even
minimize Totem more
Those pictures should only visualize what I mean and Totem shouldn't look like this ... they are just made by GIMP and I think there could also be many improvements
