Would you rather have no external dependencies or have more functionality at the cost of depending on the Java Virtual Machine?

[rvost]

Current extension functionality is restricted due to the limitations of schema validation using XSD 1.0. Certain constraints in CE files cannot be expressed in XSD 1.0. Improvement may be possible with XSD 1.1, but it is uncertain when the XML language server will provide support for it.

So the only way to further improve validation and completion is to write an extension to the XML language server. This is much more work for me and puts the burden of external dependency on the user. Extensions to XML language server require Java to be installed on the user's machine.

Since the dependency on Java may be controversial, I'm interested in your opinion first.

[wrdg]

Can this not be accomplished through TypeScript? Rather than relying on a runtime that needs to be installed by the user?

[rvost]

Currently, all the heavy lifting is done by the Redhat XML extension and its language server. My extension is just configuration for it and some wiring for modded files. I'm still researching options, but it looks like the JS ecosystem has far less support for XML and I'd prefer to avoid reinventing language server when we already have one.

[wrdg]

Ah I see now...

External extensions are not built into LemMinX but instead are contributed via an external JAR.

Well at least its minimum requires JRE 8, so it's not a train wreck to get users to install a supported runtime.