##### A — NO SESSION: the visitor's own language
  settings.json language before: (unreadable)
  /login with no cookie      -> html lang=<html lang="hu"
  globe present on /login    -> 0
  POST /lang lang=en back=/login -> 302   /login WITH the cookie     -> html lang=<html lang="hu"
  and an English phrase      -> 0
  settings.json language after:  (unreadable)
  POST /lang lang=xx         -> 302
  POST /lang back=//evil     -> /login?next=%2Flang
  /claim and /recovery globes: /claim=0 /recovery=0 
##### B — WITH A SESSION: the household's own setting, cookie NOT read
  /launcher with session + the en cookie -> html lang=<html lang="hu"
  the footer: version, globe, sign-out in order -> 
  the OLD text links are gone -> lang-switch-btn count = 1
##### C — the saved notes, as they stand on this box
