Apostolica Sedes Vacans: Crest of the Vacant See

Anyone who has visited the Vatican website lately has seen this crest on the homepage. This is the crest of the Vacant See. Usually, the Apostolic See’s crest is this image with the triregno (the three-tiered papal crown) without the umbracullum (better known as the ombrellino; it’s the umbrella). The triregno is obviously a symbol of the Pope, however, where does the ombrellino fit in?

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