The project is copy from https://github.com/BlanCow/YouTube-Comment-Translate for Youtube.
After installing, this icon will appear next to every comment
The default target language is your browser language. To change it, click in the top right corner of firefox on the extension icon:
and select a new target language by clicking on the dropdown:
The changes are applied instantly so no need to refresh the youtube page
Simply download the extension from https://addons.mozilla.org/en-US/firefox/addon/youtube-comment-translate/ for Firefox or from https://chromewebstore.google.com/detail/youtube-comment-translate/inkldemkdmcdgjdjgbimjkfafpgibaha for Chrome.
For developers who want to fork my project, after making a change, you must build the extension for the browser of your choice (currently only firefox and chrome) with the following command:
powershell ./build-extension.ps1 {{ BROWSER_NAME }} (Windows 10+ is required)
The command minifies inject.js, create a different manifest.json file depending on the browser and generates a zip file and folder containing the extension data that you can upload to the browser.