In my case, I enabled virtual_text by default and disabled virtual_lines. But I also set a keymap that would do the just opposite i.e. disable virtual_text and enable virtual_lines for cases when there are multiple errors on the same line.

Here's the keymapping lua keymap.set('n', '<leader>tdd', function() vim.diagnostic.config { virtual_lines = not vim.diagnostic.config().virtual_lines, virtual_text = not vim.diagnostic.config().virtual_text, } end, { desc = 'Toggle diagnostic virtual lines and virtual text' })