Why can't I edit my profile, interests, or entries? How do I set my default encoding?
This is rather vague; the FAQ is actually about the "Bad Unicode Input" error and "Invalid Text Encoding" errors, the first of which doesn't even mention a 'default encoding' (I'm not sure if the second does or not):
Your browser sent some text which is not recognised as valid text in the UTF-8 encoding, as it should be. This might happen if you forced your browser to view the previous page in some other encoding rather than UTF-8. It may also indicate a bug in the browser. If you cannot get around this error, contact us.
I think the question should be changed to something similar to:
Why do I receive a "Bad Unicode Input" or "Invalid Text Encoding" error?
This puts the errors themselves in the FAQ, making it much more obvious what to look for, and also puts it in the same format as the other error FAQs (eg. Why do I receive an "irreparable invalid markup in entry" error?, etc)