The perform import message copies tiddlers from a specified plugin into the main store. See the UpgradeMechanism for an overview of how it is used by the core.
|Title of the pending import tiddler. Defaults to $:/Import
To select which tiddlers are to be imported, fields with names formed from
selection- plus the title of the tiddler are used. The value unchecked causes the tiddler to be skipped from the import.