Access to fetch at 'https://geolonia.github.io/simple-geocoder/api/13/13101/131010002001.json' from origin 'https://community-geocoder.geolonia.com' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.
サンプルに入っている「東京都千代田区霞が関1-3-1」で検索しても,緯度経度が表示されませんでいした。エラーを見ると,
Access to fetch at 'https://geolonia.github.io/simple-geocoder/api/13/13101/131010002001.json' from origin 'https://community-geocoder.geolonia.com' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.
https://geolonia.github.io/simple-geocoder/api/13/13101/131010002001.json net::ERR_FAILED
となっていました。 環境はWindows10 Pro, Chrome 83.0.4103.61(Official Build) (64 ビット)です。