[Affected versions]: Nightly 63.0a1 [Affected platforms]: Mac OS X 10.13, Windows 10 x64 [Prerequisites]: - set the pref dom.payments.request.enabled to "true" - have a profile without saved cards [Steps to reproduce]: 1. Go to “https://rsolomakhin.github.io/pr/contact/” and click on “Buy” button 2. Click on “Add” for new Contact Information 3. Fill in all the field with data except de required (first name) one 4. Click on Save 5. Check the dropdown list of contact informtaion [Expected Result]: The “Save: button should be grayed out and not allow to save the contact information without the required field completed. [Actual Result]: The contact information data is saved if all the field are completed (or some of them) while the required one is not. [Notes]: If the “Save” button is clicked while there are no fields completed at all the “There was an error saving the address.” message is displayed, which is as expected.

This will probably be fixed by bug 1476345 but I'll follow-up.