no pop up is shown after adding to cart

-- HikaShop version -- : 4.0.0
-- Joomla version -- : 3.9.0
-- PHP version -- : 7.1.14
-- Browser(s) name and version -- : firefox 63.0 (64-bit)
-- Error-message(debug-mod must be tuned on) -- : no error message, just no pop up

I disabled mootools because it slows the site down too much. Now I use pop up mode vex and image pop up mode shadowbox (external) but the pop ups do not show. Also the T&C do not appear when the user clicks on that link during check out.

Hello,

You should not use the "add to cart legacy" anymore but use the new system instead (with the "cart notification" plugin for the popup)
www.hikashop.com/support/documentation/5...html#advanced_legacy

And I would also recommend you to use the new checkout system and not the legacy one.

Regards,