In Shrek there is a scene in which Shrek gets shot in the butt with an arrow. To distract Donkey Fiona sends Donkey into the woods to find a blue flower with red thorns. Donkey exclaims that it would be easier to do if he wasnt colorblind. Is Donkey actually colorblind or was this a mistake by the film creators. 

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  [1]: https://i.sstatic.net/mzWGV.jpg