old_contents: $(function() {
  	$('#followButton').click(function() {
  		var $button = $(this);
  		$button.attr('disabled', true);
  
  		if ($('html').data('is-following') == true) {
  			$.ajax('https://api.misskey.xyz/users/unfollow', {
  				type: 'delete',
  				data: { 'user_id': $('html').data('user-id') },
  				dataType: 'json',
  				xhrFields: {
  					withCredentials: true
  				}
  			}).done(function() {
  				$button.attr('disabled', false);
  				$button.removeClass('following');
  				$button.addClass('notFollowing');
  				$button.text('フォロー');
  				$('html').data('data-is-following', 'false')
  			}).fail(function() {
  				$button.attr('disabled', false);
  			});
  		} else {
  			$.ajax('https://api.misskey.xyz/users/follow', {
  				type: 'post',
  				data: { 'user_id': $('html').data('user-id') },
  				dataType: 'json',
  				xhrFields: {
  					withCredentials: true
  				}
  			}).done(function() {
  				$button.attr('disabled', false);
  				$button.removeClass('notFollowing');
  				$button.addClass('following');
  				$button.text('フォロー中');
  				$('html').data('data-is-following', 'true')
  			}).fail(function() {
  				$button.attr('disabled', false);
  			});
  		}
  	});
  });
new_contents: $(function() {
  	$('#followButton').click(function() {
  		var $button = $(this);
  		$button.attr('disabled', true);
  
  		if ($('html').data('is-following') == true) {
  			$.ajax('https://api.misskey.xyz/users/unfollow', {
  				type: 'delete',
  				data: { 'user_id': $('html').data('user-id') },
  				dataType: 'json',
  				xhrFields: {
  					withCredentials: true
  				}
  			}).done(function() {
  				$button.attr('disabled', false);
  				$button.removeClass('following');
  				$button.addClass('notFollowing');
  				$button.text('フォロー');
  				$('html').data('is-following', 'false')
  			}).fail(function() {
  				$button.attr('disabled', false);
  			});
  		} else {
  			$.ajax('https://api.misskey.xyz/users/follow', {
  				type: 'post',
  				data: { 'user_id': $('html').data('user-id') },
  				dataType: 'json',
  				xhrFields: {
  					withCredentials: true
  				}
  			}).done(function() {
  				$button.attr('disabled', false);
  				$button.removeClass('notFollowing');
  				$button.addClass('following');
  				$button.text('フォロー中');
  				$('html').data('is-following', 'true')
  			}).fail(function() {
  				$button.attr('disabled', false);
  			});
  		}
  	});
  });
subject: Fix typo