Remove formatting of headings in the widget

My H1 is approx 50px

When I go to format my other text I cannot select H2 H3 or H4 because those options are obscured by the H1 option.

This seems to happen because the formatting widget displays the fonts as their real life sizes. When an H1 is larger than 24px+ then this is happening for me.

How do I stop the formatting from carrying over into the widget? It doesnt seem to be how this should work. Any tips or suggestions would be great.

Cheers… Brett