Jigsaw blocks and other half-implemented features (Java Parity)

Many features are set out on Bedrock edition, however not properly implemented. Jigsaw blocks and custom biomes are both things I've found knowledge bases and documentation of, only to realise Jigsaw blocks don't work, and custom biomes are broken. Many things like this give me false hope, an with how many years they have been sitting there, incomplete, gives the feeling that Bedrock edition is being neglected due to not having as many outspoken individuals being heard online. Please at least consider fixing some of these features, as there is a lot of opportunity just out of reach.