Is it possible to move the navigation panel on left side to either the top (convert to more horizontal layout) or right so there is not a couple inch gap on left after you scroll down a little on the screen .
The suggestion is to allow larger text when using browser or OS scaling feature on the thread summary view without the right side of thread summary section going off the right screen as quickly. I use a 22-inch screen in 1920x1080 and scale screen text to 125% (settings in screen shot). My eyes are not as good as they used to be.
Screenshot with view scaled to see entire view.

The other idea is to reduce the white space in thread title section by removing some of the fixed space. Refer to area highlighted in green in attached screen shot. Very few threads have titles that use the
entire space.
When in a specific thread, the thread text area always stays completely on screen no matter screen scaling (a good thing). When in reply window, it does not. This is where moving navigation panel would help.