I see 2 possible problems in the code above:
1) Look if single quote “‘” is not replaced at your copy with other characters;
2) at the JavaScript code line
var fields_to_disable = ['role', 'facebook', 'twitter', 'additional_profile_urls', 'wp-user-avatar-existing,];
there is a syntax error. Replace the ‘,’ at the end with missed “‘” (closing single quote) character, like below:
var fields_to_disable = ['role', 'facebook', 'twitter', 'additional_profile_urls', 'wp-user-avatar-existing'];