ENIGMATICO 
As a non-native english speaker I always have difficulties with some regional dialect words, like 'color' and 'colour', or 'favorite' and 'favourite'. The British like to add an U to these words. I don't know which one to use since I'm neither so sometimes I use one, other times I use the other.
Hagarashi8@enigmatico As a fellow non-natuve, I don't think that matters. People online at least seem to understand both, so don't waste your time overthinking it and use whatever feels natural.