Backline pane in 0.7.1 has more flexibility which can be displayed as a side-pane or as a note-pane.
I turn to set a smaller font-size for side pane than that for note-pane. Considering the different width. Currently, from what I can see (I may be wrong), both modes of backline panes share the same class/id structure.
It would be great to give them distinguishable labelling to allow flexible customisation.