Problem:
vim.lsp.completion.enable(true, client.id, bufnr)
vim.lsp.completion.enable(false, client.id, bufnr)
Error detected while processing LspDetach Autocommands for "*":
Error executing lua callback: …/lsp/completion.lua:701: Vim:E367: No such group: "vim/lsp/completion-22"
stack traceback:
[C]: in function 'nvim_del_augroup_by_name'
…/lsp/completion.lua:701: in function 'disable_completions'
…/lsp/completion.lua:724: in function 'enable'
Solution:
Delete the correct augroup.