Flash Cardon is a free Chrome extension developed by aquilax that turns any web page into a language learning experience. With this extension, users can build their vocabulary by keeping track of known words and highlighting new ones to learn. The collected vocabulary can be exported as structured text and used to create flashcards.

Using Flash Cardon is easy. Simply open a web page in the language you want to learn and click on the Flash Cardon icon on the top of the browser. All words that are not added will get a yellow highlight background. Double-click on a word to add or update its meaning. Additionally, users can see some statistics in the lower right corner of the page.

The extension also allows users to export, import, and update vocabulary. To do so, right-click on the Flash Cardon icon and select Manage Words from the popup menu.

Overall, Flash Cardon is a useful tool for language learners who want to expand their vocabulary in a simple and organized way. The extension is easy to use and provides useful features for tracking and managing vocabulary. It is also worth noting that the source code is available on GitHub for those interested in contributing to the project.