Disable lsp in diff

When I start diff using

nvim -d fileA fileB

my lsp shows a ton of errors. I am not interested in lsp errors when I diff; I would like them to disappear. I can stop lsp in the first window with :LspStop then I need to jump right <C-w>l and type again :LspStop. How can I automate it? Preferably in a way that I don’t need to type anything when I run diff.


What I have for now is this remap

vim.keymap.set("n", "<leader>diff", "<cmd>LspStop<CR><cmd>set signcolumn=no<CR><C-w>l<cmd>LspStop<CR><cmd>set signcolumn=no<CR>");

It does the job. The signcolumn=no hides the space where lsp would display error signs. My leader is space

vim.g.mapleader = " "

It’s okay but I would like to have something like the autocmd BufNewFile except that the command is not issued at the loading of a new file but when nvim starts in the diff mode.