Starting from version 1.12.0 sing-box added tls fragment to its core. Panel is now providing fragment sub for sing-box, however, please note that fragment settings in panel are not affecting sing-box config because it only has 1 mod available and is not flexible. It works by the way.
Warning
Please use 1.12.0-beta.28 or higher versions of sing-box.
- Fixed Russia routing rules bug.