Wiki hacks

# Allow external images
$wgAllowExternalImages = true;

# Prevent new user registrations except by sysops
$wgGroupPermissions['*']['createaccount'] = false;

# Restrict anonymous editing
$wgGroupPermissions['*']['edit'] = false;


$wgMetrolookDownArrow = false;
$wgMetrolookUploadButton = false;

https://www.mediawiki.org/wiki/Skin:Metrolook#Customization