Wavebox supports installing extensions directly from the Chrome Web Store. (https://chrome.google.com/webstore/category/extensions). Here's how you can install an extension

  1. Open a new tab in Wavebox, either by using the window menus or the New Window button in the sidebar
  2. Find the extension you want to try in the Web Store https://chrome.google.com/webstore/category/extensions
  3. To use, click Add to Wavebox

More information on How to add, delete and manage Chrome extensions