Every once in a while I see text in Arabic in MTGA, even though I've set it to English. I've never used MTGA in Arabic, my system language is Swedish and has never been Arabic, and I've never been to any Arabic speaking country.

Edit: It turns out this isn't Arabic, it's Phyrexian, a constructed language invented specifically for MTG. Maybe it could be useful then to add somewhere where it says that that's Phyrexian so that people don't get confused.