mastodon/tsconfig.json

{
  "compilerOptions": {
    "jsx": "react",
    "target": "esnext",
    "moduleResolution": "node",
    "allowJs": true,
    "noEmit": true,
    "strict": true,
    "esModuleInterop": true,
    "skipLibCheck": true,
    "baseUrl": "./",
    "paths": {
      "mastodon": ["app/javascript/mastodon"],
      "mastodon/*": ["app/javascript/mastodon/*"]
    }
  },
  "include": [
    "app/javascript/mastodon",
    "app/javascript/packs",
    "app/javascript/types"
  ]
}