Interesting stats, thank you.
I probably expressed myself badly or maybe it's still confused for myself but I don't want to discriminate users via PC, I told myself that since the majority of visitors are generally via small screens, I might as well put themselves from their point of view to create and organise a forum...
It may be an unfortunate idea, I don't know. Anyway, XenForo is so made that anyway, with the basic style, no matter the size of the viewport then the display is good for the user.
In absolute terms, I imagined myself to be a better forum manager if I managed everything via mobile since I am closer to users from the point of view of user experience. It's probably wrong said like that, literally. But there is a "je ne sais quoi" lying around in my head... 
—-
The initial question had a technical basis (I no longer have a PC) so maybe I'm trying to convince myself...
