When hovering over "Pattern", jdt.ls returns a 122324-character hover, but the returned javadoc is truncated at 10000 characters by VS Code.
pattern_hover_response.txt.
In the past (2020), VS Code could render the Pattern Javadoc without any issues:

1- we need to figure out if there's a way for vscode to cope with large hovers
2- the rendered markdown shows very large amounts of whitespace characters in use somehow, there might be some optimization possible there.