missing argument guibg=

[Maddin-619]

Today after updating I got these error message:

The error also appears with the default style.

Figured out, that hl.bg passes the vim.validate function (not nil) but is an empty string. Maybe we should check that too:

  if hl.bg ~= nil and hl.bg ~= "" then
    table.insert(cmd, 'guibg=' .. hl.bg)
  end

[nanozuki]

Thank you! I fixed it.