There's no rule to regulate how a character posts to the internet. I had a wizard who thought his laptop was an enchanted book but it turned out to be from a neighboring dimension that existed in his canon (That was Owyn). Silver uses a Pokedex, Garrett was from a steam punk universe so he used a "Mechanist Device" that granted him access to DDD but not the internet at large. Those are all MY characters, of course, people use their imagination for the computer issue.