Responsive Typography - Live Preview is incorrect with Custom Page Headers

[nicolepaschen]

1. Have one Custom Page Header set to the homepage and another one set to everything else
2. Use a Headings Typography font with a font weight other than normal
3. Enter a standard Font Size and Responsive Font Size for large desktop, small desktop, and tablet
4. Publish and close the Customizer
5. Reopen Customizer and change standard Font Size
6. Live Preview updates to show the new value when the responsive font size should be used in the live preview
   

[nicolepaschen]

when I change the standard font size the live preview changes even tho I since I have a responsive font size entered it should not.

since the screen is large desktop and I have a large desktop responsive size set, the live preview shouldn't change when I change the default value since that isn't affecting my current screensize