I've always set
LSUIPresentationMode to 4 in iTerm and Firefox to hide the annoying unnecessary menu bar taking up precious vertical space on my macbook.
If I needed the menu, I could just move my mouse to the top of the screen, and it would appear. The rest of the time that space was used by the terminal and the browser.
After an upgrade to Yosemite this features no longer works. Most of the time setting this option to 4 or 3 (hide completely) does nothing. Sometimes it crashes the app. Sometimes the menu is hidden but the empty space is not occupied, so there's a long line on top.
This is really annoying. I submitted a bug report to Apple during the beta test - no response.
Running apps full screen is not an option. Unlike Linux implementation, OS X's full screen is not usable for me. You have to switch between spaces, you can't open other windows on top, etc.
So does anyone have an idea on how to fix this?