[Lazarus] How to use strings properly with fixes_1_6 and FPC 3.0.0?

[Jürgen Hestermann]

Am 2016-10-22 um 10:53 schrieb Mattias Gaertner via Lazarus:
 > Maybe you mean ligatures? Many languages have them, even German:
 > https://en.wikipedia.org/wiki/Typographic_ligature

I thought that ligatures are just a matter of the font
but not the unicode representation?
When I write a text which contains the two letters "fi"
they should be two separate characters in my unicode string
no matter whether they will be printed as a ligature  on the printer or screen.
So ligatures should not influence string encoding in FPC.
Or am I missing something here?