    paper.unfreeze([opt])

Update the views of an `async` paper to make sure that the views reflect the cells' models; unfreeze the paper afterward.

Several extra arguments may be provided in the `opt` object:

batchSize | number | For `async` papers, how many views should there be per one asynchronous process? Default is `1000`.
progress | function | Callback function that is called whenever a batch is finished processing. The callback function is provided with three arguments:
done | boolean | Are we done? Was this the last batch?
processed | number | How far along are we? How many elements have been processed as part of a batch so far?
total | number | How many views are there? How many elements in will have been processed as part of a batch when we are done?
viewport | function | Callback function to determine whether a given view should be added to the DOM. By default, `paper.options.viewport` is used, but you may provide a different callback function. The format of the callback method is described in the option's documentation, as are examples of usage.
beforeRender | function | Callback function executed before processing scheduled updates. By default, `paper.options.beforeRender` is used, but you may provide a different callback function. The format of the callback method is described in the option's documentation.
afterRender | function | Callback function executed after all scheduled updates had been processed. By default, `paper.options.afterRender` is used, but you may provide a different callback function. The format of the callback method is described in the option's documentation.

Use `paper.freeze()` to freeze the paper again.