Method 1. Follow https://myjian.github.io/mai-tools/#howto
Method 2. Install the userscript: https://github.com/myjian/mai-tools/blob/gh-pages/install-mai-tools.user.js . Your browser must support Tampermonkey or other userscript managers before you can install the userscript. Once the userscript is installed, mai-tools will be loaded automatically on every maimai-NET page.
npm install
npm run build
npm start
npm run watch
npm start
Using SourceGraph https://sourcegraph.com/search?q=context%3Aglobal+repo%3A%5Egithub%5C.com%2Fmyjian%2Fmai-tools%24+GameRegion&patternType=standard&sm=1&groupBy=path (replace GameRegion with whatever you want to find)