The best, most interactive and best UX design for a "book recommendation plugin" shall be one that has an app-like design. An app-like design includes clear icons, buttons, tabs, and navigation that can be accessed at any time. A book recommendation plugin should also have an easy-to-use interface that is easily navigable.

This shall provide them with a greater sense of satisfaction that they are recommending books that they enjoy to other people.

Unfortunately, there is no plugin that can provide you these features but you can achieve it using custom code.

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