A small firefox extension written in JS to check if a manga is licensed or not in english, check on any https://mangadex.org/title/ if the manga is licensed ! You have to refresh once on the title page to get the info (due to trouble with dinamicall refresh Nuxt.js on mangadex,you have to refresh the page manually to get the info ! Working on a fix)
Don't you ever find it annoying to have to look if a manga is licensed in English to buy it , well you are at the right place !
This extension use the MangaUpdate API : https://api.mangaupdates.com/
Working on it to get it better
Addon : https://addons.mozilla.org/en-US/firefox/addon/mangadex-licensed