CSS pseudo selector :active (alias :highlighted) broken when btn created with FormattedString

Example
main-page.xml

<Button (tap)="login()" >
            <FormattedString>
                <Span [text]="loginText + '\n'" fontSize="28"></Span>
                <Span [text]="descText" fontSize="12" ></Span>
            </FormattedString>
</Button>

main-page.css

Button {
    background-color:#1b1d1d;
    color: #E8EAEB;
}

Button:active {
    background-color:#E8EAEB;
    color: #1b1d1d;
}

Note: The case seems to be reproducble only when using Button global styles in app.css and a Button created via FormattedString

app.css

Button {
    color: #343838;
}

Demo application demonstrating the above case canb e found here

Broken with tns-core-modules 5.0.0 - working with 4.2.0

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