json: omni completion (schema values) doesn't work

[kmARC]

The following should work in a package.json file where | is the cursor, and triggering omni completion <i_Ctrl-X_Ctrl-O> would propose "author":

{
    "au|
}

Instead, "Pattern not found".

how to reproduce

Minimal vimrc:

set nocompatible

call plug#begin('~/.vim-debug/plugged')
Plug 'prabirshrestha/vim-lsp'
Plug 'mattn/vim-lsp-settings'
call plug#end()

function! s:on_lsp_buffer_enabled() abort
  setlocal omnifunc=lsp#complete
endfunction

augroup lsp_install
  au!
  autocmd User lsp_buffer_enabled call s:on_lsp_buffer_enabled()
augroup END

Example:

vim -u ~/.vim-debug/vimrc package.json

:LspStatus
vscode-json-language-server: running

I also tried with explicit schema, same problem:

{
    "$schema": "https://json.schemastore.org/package.json",
    "au|
}

remarks

• Other languages (tried python) work perfectly with the same minimal vimrc.
• :LspSettingsLocalEdit and :LspSettingsGlobalEdit are both empty.
• vim-lsp-settings version: 4f8471d (Mon Jan 13 16:01:08 2025)
• vim-lsp version: 04428c9 (Mon Sep 23 01:16:10 2024)
• vim version:

  VIM - Vi IMproved 9.1 (2024 Jan 02, compiled Mar 02 2025 21:28:22)
  Included patches: 1-1165
  Compiled by Arch Linux