Bootswatch Previewer Legacy is a Chrome extension that allows users to preview any Bootswatch theme on their Bootstrap website directly from the browser. Developed by Kobi Tate, this free add-on falls under the Browsers category, specifically the Add-ons & Tools subcategory.

With Bootswatch Previewer Legacy, users can easily experiment with different themes and see how they would look on their Bootstrap v3 website. This legacy version is designed specifically for Bootstrap v3, providing compatibility and ease of use for those using this version of the framework.

The extension simplifies the process of theme selection, giving users the ability to instantly preview and switch between themes without the need for any coding or manual theme installation. It's a handy tool for web developers and designers who want to quickly visualize how different themes would affect the overall look and feel of their Bootstrap website.

Please note that if you are using Bootstrap v4, you will need to download the corresponding version of Bootswatch Previewer from the Chrome Web Store.