renamed card still exists+example

Renamed sidebar to customizable sidebar, but...sidebar still shows a card (with an odd but unsurprising error for +tickets for item :-).

Didn't try deleting it again, wanted to leave it in this state.

(Later) Aargh, i forgot about this and ended up creating it again, which overrode this error. +tickets for item made some reference to the card not existing. Anyway, hopefully whatever this bug was is related to some of the other renaming/ghost card issues.