Motivation for this change

There is a bug in Pidgin which seems to happen due to a bug in Pango.

I have only tested the patch by using a custom derivation:

pkgs.pidgin.override {
  gtk2 = (pkgs.gtk2.override {
    pango = (pkgs.pango.overrideAttrs (old:
      {
        patches = old.patches ++ [
          (pkgs.fetchpatch {
            url = "https://gitlab.gnome.org/GNOME/pango/-/commit/948e0b0cb5319adfa956f08c40dd1ea85855a424.patch";
            sha256 = "03vhqpnsq6gzvsd0sz7n5126zrp1b4kfbbfmhc1pmay3rp2ifz7w";
          })
        ];
      }));
  });
}

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option sandbox in nix.conf on non-NixOS linux)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Determined the impact on package closure size (by running nix path-info -S before and after)
• Ensured that relevant documentation is up to date
• Fits CONTRIBUTING.md.