The information of ChessBase support is wrong in my opinion.
Reasons:
* Variant has a different meaning to the one used today. See the [commented specification about Variant tag](github.com/mliebelt/pgn-spec-commented/blob/main/pgn-specification.md#932-tag-variation) for details.
* All major chess sites (chess.com, lichess.org, chesstempo, ...) are using the Variant tag in different ways. This may depend on what is available on the websites themselves (e.g. lichess uses the variants that are available on their website), but there is currently not defined a (final) list of "allowed" variants. See http://w01fe.com/berkeley/kriegspiel/notation.html for one usage, or lichess.org/analysis/racingKings#1 for another one.
It is a pity that one of the major chess companies does not allow the full use of the PGN specification. Hopefully some of them reads that interesting thread.
Reasons:
* Variant has a different meaning to the one used today. See the [commented specification about Variant tag](github.com/mliebelt/pgn-spec-commented/blob/main/pgn-specification.md#932-tag-variation) for details.
* All major chess sites (chess.com, lichess.org, chesstempo, ...) are using the Variant tag in different ways. This may depend on what is available on the websites themselves (e.g. lichess uses the variants that are available on their website), but there is currently not defined a (final) list of "allowed" variants. See http://w01fe.com/berkeley/kriegspiel/notation.html for one usage, or lichess.org/analysis/racingKings#1 for another one.
It is a pity that one of the major chess companies does not allow the full use of the PGN specification. Hopefully some of them reads that interesting thread.