Hello!
I have my master locale in Prismic set to Norwegian, in my uid field for e.g. my page types "posts" I am allowed to use "æ" and "ø" but not "å", when I type "å" it's automatically transformed into "a". Is this a bug or intentional?
Thanks 
The uid field is most commonly used to generate URLs. To ensure compatibility with URL structures, as they don't support special characters they are automatically transformed to their closest equivalent.
Yes, it's intentional.