I have this line in my init.el file to set the size of the font in all frames:
(push '(font . "DejaVu Sans Mono-10") default-frame-alist)
It works but i'd like to have a bigger font in all buffers while keeping a smaller one for the mode line (so it could fit more information and be less distracting). The idea is to have this set automatically without having to change the font size with C-x C-+ for every open buffer.
I'm using Emacs 126.96.36.199 compiled from trunk on a GNU/Linux system.
Edit: just added an answer showing how it can be done.