Filters update error · Issue #5404 · AdguardTeam/AdguardForAndroid · GitHub: https://github.com/AdguardTeam/AdguardForAndroid/issues/5404
Let’s Encryptがクロス署名を廃止すると発表、証明書のデータ量が40％削減される一方でAndroid 7.0以前の端末では対応が必要に - GIGAZINE: https://gigazine.net/news/20230711-lets-encrypt-cross-sign/
Shortening the Let's Encrypt Chain of Trust - Let's Encrypt: https://letsencrypt.org/2023/07/10/cross-sign-expiration

https://www.sslshopper.com/ssl-checker.html#hostname=filters.adtidy.org
> Organization: Let's Encrypt