Is it possible to use non-free components in open source software?

Question

Licenses for software and other works

For example, there is a server under the GNU GPL v3 with scripting support (Squirrel/Pawn), can these scripts be not free?

Answer 1

IANAL, TINLA.
Here you need to clarify what you have going on there. If there is a free interpreter covered by the strong copyleft of the GNU GPL that you want to run non-free scripts with, then for heaven's sake.
A well-known example to you: GNU Bash (as well as, for example, Busybox Ash) - the interpreter is distributed under the terms of the GNU GPL, but this in no way limits your ability to write non-free scripts in their language.
But if, for example, the functionality of a script depends on a library under strong copyleft, then it falls under this copyleft, completely irrespective of what is happening with the interpreter.
For example, a Perl program (it's under the Artistic License v1 || GNU GPLv1+) that uses the featuresGhostscript (it's under the GNU Affero GPL ) is copyrighted by the GNU AGPL and should be free.