# Compatibility Notes

## Input Normalisation

- Lines that begin with `#`, `;`, or `//` are ignored before parsing, matching the legacy subconverter subscription behaviour.
- UTF-8 byte order marks and common zero-width spacing characters are stripped so mixed-encoding lists no longer yield false negatives.

## Legacy Scheme Support

- Subscription items prefixed with `vmess1://` are normalised to standard `vmess://` links.
- `socks://` URIs and Telegram sharing links (`tg://socks`, `https://t.me/socks`) are accepted and converted into Socks5 nodes during parsing.
- Existing `ss://`, `ssr://`, `trojan://`, and HTTP subscription lines continue to work without modification.

## API Flags

- A new `ipv6` query parameter is honoured by the conversion pipeline and generator layer. Supplying `?ipv6=true` enables IPv6 sections in supported outputs without forcing a global default.

## Manual Verification Checklist

1. `go test ./internal/conversion -run LegacyProtocols`
2. `go test ./...`
3. Start the server (e.g. `go run ./main.go --config config.yaml.example`) and request `curl "http://localhost:25500/api/convert?target=clash&url=<sub-url>&ipv6=true"` to confirm the response reports `request_options.ipv6=true`.
4. Inspect the logs while submitting a subscription that includes `socks://` and `vmess1://` entries to ensure they are parsed successfully and appear in the generated profile.