Dymanic capability registration not enabled, helix-editor reports

[Tefached95]

Hello,

I've been trying to get the LSP working with the helix editor. I've built the server as per instructions and added the following to languages.toml:

[[language]]
name = "haxe"
scope = "source.haxe"
injection-regex = "^Haxe$"
file-types = [ "hx", "hxml" ]
comment-token = "//"
language-servers = [ "haxe-lsp" ]
roots = [".gitignore"]

[language-server.haxe-lsp]
command = "node"
args = ["E:\\Projects\\haxe-language-server\\bin\\server.js"]

[[grammar]]
name = "haxe"
source = { git = "https://github.com/vantreeseba/tree-sitter-haxe", rev = "ca7ed7931a93a0434cd1f5d6bb6c333865fe711a" }

Which "works", but then trying to open a .hx file results in the following output in the log:

2023-06-14T19:08:16.693 helix_lsp::transport [ERROR] haxe-lsp err: <- StreamClosed
2023-06-14T19:08:16.766 helix_term::application [WARN] Ignoring a client/registerCapability request because dynamic capability registration is not enabled. Please report this upstream to the language server

If more details are needed please let me know, and thank you in advance!