Get rid of the additional header when viewing a file (pdf, excel, word) and not editing. This hogs a ton of screen space, even in the 'expanded tab' view and does not add any value to the experience.
Screenshot for clarification.
A McPherson commented
Absolutely!!!! I can't believe this hasn't got more votes
I've attached a similar example. In my case,
A) the entire red circled section isn't needed.
B) The header circled in Blue could be made smaller
C) Blue Word Heading (circled in Green) isn't needed either.