So I recently got an lg 2560x1080 monitor and I love it. The only problem is that when playing fallout 4 the pipboy is shrunk making it really annoying to manage. Does anyone know of a way to fix this issue. If it helps, to get the 21:9 compatibility I just edited the prefs ini file.
I used to play Fallout on my 21:9 monitor before I bought a new 4K one and can't say I noticed any issues with the pipboy but I only played Fallout at 21:9 up until that point.
There is mods that fix the UI for the 21:9 aspect ratio such as this: http://www.nexusmods.com/fallout4/mods/274/? which may include a fix for the pipboy.
Also if you use Power Armour you may want to use this mod as well: http://www.nexusmods.com/fallout4/mods/178/?. It removes the metal UI element from the Power Armour and the readme includes a fix which allows you to stretch the Power Armour UI to better fit the aspect ratio.
Next time you start up the game, after you load your save, open up the console, type "fov 90" or whatever you prefer. After that, type "refreshini" to reload your edits to the ini files. It'll set the fov back to where you had it without affecting the fov when the pip-boy is up.
I think I have my fov set to 110, with my pip-boy fov set to 80, but I set it so long ago, I hardly remember.