ChromeXt app
ChromeXt is Xposed tool that is open source under the GPL-3.0-only license.ChromeXt adds UserScript and Dev Tools support to Chrome using Xposed framework.
Once installed, you can install UserScripts from popular sources: URLs that ends with .user.js. However, this fails for scripts from some domains like raw.githubusercontent.com. For them, please download those scripts using the download button on the top of Chrome's three dot menu, and then open your downloaded scripts in Chrome. The installation prompt should show up again. Alternatively, it is possible to use the Install UserScript page menu if you simply want to install it without further editing.