Once you have toggled a few items on and off there is no way to get
back to the shipped layout short of remembering which ids are in
STATUSBAR_HIDDEN_BY_DEFAULT. Add a row to the bar's right-click menu
that restores that set.
The row is disabled rather than hidden when nothing is customized, so
it also advertises that a shipped layout exists. Reset touches item
layout only — whole-bar visibility is a separate preference, and
resetting from the bar's own menu should not make the bar you are
right-clicking disappear.