Hi, I have 2 problems after update app to {N} 2.4 (Android 7.0, Angular2)

1. I can't set transparent border to button. When I try to set border-color: rgba(0, 0, 0, 0); it appeared as black border, but when I try border-color: rgba(0, 0, 0, 0.1); it works fine
2. I can't set background color to white on custom dialog. When I try to set this.page.backgroundColor = new Color('rgb(255,255,255)'); or just 'white', dialog appears without any background (transparent). Also without setting any custom background, it appears as transparent. But when I try this.page.backgroundColor = new Color('rgb(250,250,250)');, it works.