o-ey is a Chrome add-on developed by kiwiyou.dev. It is a user translation viewer for BOJ (Baekjoon Online Judge), a popular online judge system for coding problems. This add-on allows users to view user translations from the boj-user-translation repository directly on the BOJ problem page.

When users translate problems on BOJ, these translated problems are marked as yellow on the problem listings. With o-ey, users can simply click the language button on the problem page to view the translation. The add-on also provides a convenient way to add your own repository for translation, by clicking the extension button and adding your repository to the list.

Additionally, users can access the index of translated pages on the boj-user-translation repository on GitHub. It is worth noting that the list of translated problems can also be seen on the solved.ac website.

Overall, o-ey is a useful tool for BOJ users who want to access user translations easily and conveniently while solving coding problems.