[Koha] Field 773 $t not editable in any framework

[Mark Tompsett]

Greetings,

The field may not be editable directly, but when I encountered something 
similar (not this field specifically) the other day, I discovered that there 
was a little icon beside the field that popped up a page which let me build 
what was needed to fill in the data. That's just my suggestion without 
looking, so take with a grain of salt. Though, if true, it is far better 
than directly editing the data. :)

GPML,
Mark Tompsett