What is the key?

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How are the above links here?

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This page contains details about Fallen London Actions.

From: The Hidden Refuge

Action Cost: 0

How can gooseberry open a door?


Parabola remembers

The Viscountess purrs, softly. "The place we are going is strongly linked to an old friend. Gooseberry was — is – their favourite fruit. Parabola makes use of such associations. Do not worry, it will serve our purposes."