When a form field is set as ‘required’, Firefox automatically shows a red border, even before the user interact with the form. This may give the impression that the form validation is different in Google Chrome and Firefox, but this is not the case.
If you want to hide the red border in Firefox, you will need to use a CSS Theme with the following CSS style:
.form-control {
box-shadow: none !important;
}
That’s it!