Whether a value may be used as the route a learner returns to after
signing in.
Parameters
value: string
The candidate next, without the locale prefix
Returns boolean
true when the value is a safe personal path
Remarks
The account pages carry the interrupted route in a next query parameter,
which anyone can edit. Only safe, locale-less personal paths are accepted,
with or without a query string, so a crafted value can never redirect off
the site or onto a public page.
Whether a value may be used as the route a learner returns to after signing in.