We understand that it can be frustrating to try and checkout or browse a website that does not work. Not all websites are main equally and not all browsers are made equally.
This is a common issue with browsers that allow extensions. Allowing extensions in a browser adds functionality specific to the user but also could interfere with website functionality as well. Trouble maker extensions mostly include pop up blockers, advertising blockers.
You can either use a different browser and or disable all browser extensions. If all else fails, please contact firstname.lastname@example.org