I have set the following. However, the logged-in user to edit, chapcha is displayed.
$wgGroupPermissions['*']['skipcaptcha'] = false; $wgGroupPermissions['user']['skipcaptcha'] = true; $wgGroupPermissions['autoconfirmed']['skipcaptcha'] = true; $wgGroupPermissions['bot']['skipcaptcha'] = true; // registered bots $wgGroupPermissions['sysop']['skipcaptcha'] = true; $wgCaptchaTriggers['edit'] = true; // Would check on every edit $wgCaptchaTriggers['create'] = true; // Check on page creation. $wgCaptchaTriggers['sendemail'] = true; // Special:Emailuser $wgCaptchaTriggers['addurl'] = true; // Check on edits that add URLs $wgCaptchaTriggers['createaccount'] = true; // Special:Userlogin&type=signup $wgCaptchaTriggers['badlogin'] = true; // Special:Userlogin after failure