Currently, if I select a paragraph of text in Word with Ctrl+Shift+Arrow down, then copy it with Ctrl+C, then switch to Studio with Alt+Tab, Studio will set the focus to the ribbon and display the keyboard shortcut mnemonics in the ribbon. Typing or pasting in the source segment is impossible. To unfocus the riboon, I need to press Alt anywhere between 1 and 4 times (this varies depending on the mood Studio is in, the position of the Moon and the amount of Earth radiation) or press Esc two times. The standard behavior is to not focus the ribbon when entering the program through Alt+Tab but to keep the focus where it was when leaving the program, i.e., the target segment.

A faster way to reproduce this, albeit without practical use, is to exit Studio with Alt+Tab and then immediately switch back to it with Alt+Tab (there's no productive use for just toggling between two programs, but this is a fast and foolproof way to reproduce the issue, which is not reproducible with other programs that follow the Windows GUI standard, which Studio does not). The Alt+Tab + Alt+Tab proof of concept will not manifest a problem if one first presses Alt+Tab, then grabs a cup of coffee, then presses Alt+Tab again. They need to be close to each other, but that's exactly how people working with the keyboard are bound to work.

Instead of completely reprogramming the ribbon or user interface code, it would be easy to add an event handler to the application that responds to the event of the application receiving focus and makes sure that the ribbon is not focused. Should be approximately 10 rows of code. Would help translators who use two hands on the keyboard instead of one on the mouse and one on the keyboard.