>>So, this worked wonderfully for the pattern validations, but the form originally still came with the password fields with red borders (the required). Is it expected and I should be contend with that behavior?
>>
>>Thanks again.
>
>You are using 'required' (html validation).. Maybe 'ng-required' ?

>>>Yes, will re-try. I thought about it.

>>>UPDATE. Changed required to ng-required="true" but got the same red underline. I think it's fine.

Maybe you can inspect the element in developer tool to figure out the model state (ng-pristine, ng-valid, ng-invalid, ...) on the password iput element, then the CSS class transitions can be useful to apply desired visual effect depending on the state, this can be a workaround.
.pure-form input.ng-pristine.ng-invalid { // desired style }