DeepL Box is a free Chrome extension developed by Susumu OTA. It falls under the category of Browsers and is classified as an Add-ons & Tools subcategory.

This extension provides translation history management, allowing users to save previous translations, view an index of translations, compare source and translation sentences, search by keyword, copy translations to the clipboard, and utilize a keyboard shortcut (`Command-b` for macOS or `Alt-b` for other operating systems) for quick translation.

To use DeepL Box, simply select the text you want to translate using either the mouse or keyboard, and then press the designated keyboard shortcut. Alternatively, you can right-click and choose "DeepL Translate" from the context menu to open the translation window.

The extension also offers customizable settings. Users can change the keyboard shortcuts by accessing the extensions setting page in Chrome, and they can modify the source/translation language and choose whether or not to split on punctuation through the extension's popup dialog.

It's important to note that the keyboard shortcut feature does not work for local PDF files, but users can still use the context menu instead. Additionally, Chrome removes newlines from selected text when using the context menu due to a limitation in the `info.selectionText` function.

For more information and access to the source code, visit the GitHub repository maintained by Susumu OTA.