Flake: add nixpkgs patch

flake.nix

@@ -106,6 +106,7 @@
           src = nixpkgs-unstable-raw;
           patches = [
             ./nixpkgs-patches/handheld-daemon-ui-init.patch
+            ./nixpkgs-patches/pr306227.patch
           ];
         };
         nixpkgs-patched = nixpkgs-raw.legacyPackages.x86_64-linux.applyPatches {

nixpkgs-patches/pr306227.patch

@@ -0,0 +1,24 @@
+From 8abd7b32202df6c492446edb05ef925af1515e18 Mon Sep 17 00:00:00 2001
+From: Dmitry Chermnykh <76gh6rvso@relay.firefox.com>
+Date: Tue, 23 Apr 2024 14:00:40 +0500
+Subject: [PATCH] nixos/plasma6: add qtimageformats to the requiredPackages
+
+This is needed for qt6 apps to be able to work with certain image formats such as .webp and .avif
+
+Closes https://github.com/NixOS/nixpkgs/issues/304523
+---
+ nixos/modules/services/desktop-managers/plasma6.nix | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/nixos/modules/services/desktop-managers/plasma6.nix b/nixos/modules/services/desktop-managers/plasma6.nix
+index 856d36b8a3030..d102ef167e314 100644
+--- a/nixos/modules/services/desktop-managers/plasma6.nix
++++ b/nixos/modules/services/desktop-managers/plasma6.nix
+@@ -74,6 +74,7 @@ in {
+         kguiaddons # provides geo URL handlers
+         kiconthemes # provides Qt plugins
+         kimageformats # provides Qt plugins
++        qtimageformats # provides optional image formats such as .webp and .avif
+         kio # provides helper service + a bunch of other stuff
+         kpackage # provides kpackagetool tool
+         kservice # provides kbuildsycoca6 tool