Script Summary: Hide search and navigation bar in Gmail. Reclaim your vertical screen space. Toggle button allows to bring back Google bars with just one click.
Why you need this
Today most screens are wide or ultra-wide. Vertical screen space is precious. Every extra toolbar or navigation menu reduces the available screen space. Google design is particularly bad: in addition to OS-level and browser-level horisontal user-interface elements (task bar, window title, tabs, address bar), Google adds at least three more bars in most of its products (+You menu, search bar, and context-sensitive tool bar). The first two are rarely used, but occupy as much as 9% of a typical modern screen. Install this script, and enjoy Gmail as if you had a bigger screen.