Shagrathanswered grow question 5 years ago Hi!
I don't know what that is but it does not seem to be anything alarming. Sometimes there is going to be weird spots, crinkled/damaged leafs and everything else but most of the time it is nothing to worry about and the plant will heal itself up!
It might be a drop of too acidic water or too strong nutrient water only 1 drop or something.
That seedling is looking happy! 👌