Uses $dir in extension files, and assumes that it remains unchanged in require_once( 'maintenance/commandLine.inc' ).
In fact, it is likely that '$dir' will be set when setting up command-line, as some extensions will use the same var.
Recommended fix: Use $CentralAuth_dir, $EmailPage_dir, etc.
global $wgCaptchaSecret;
$wgCaptchaSecret = "CHANGE_THIS_SECRET!";
-$dir = dirname(__FILE__) . '/';
-$wgExtensionMessagesFiles['FancyCaptcha'] = $dir . 'FancyCaptcha.i18n.php';
-$wgAutoloadClasses['FancyCaptcha'] = $dir . 'FancyCaptcha.class.php';
+$wgExtensionMessagesFiles['FancyCaptcha'] = dirname(__FILE__).'/FancyCaptcha.i18n.php';
+$wgAutoloadClasses['FancyCaptcha'] = dirname( __FILE__ ) . '/FancyCaptcha.class.php';
+