From dd8978e6e3c84a7d0c85ae1b50ca247218926288 Mon Sep 17 00:00:00 2001
From: Brenton Simpson <appsforartists@google.com>
Date: Sun, 18 Jan 2026 23:14:34 -0500
Subject: [PATCH] google-chrome: add plasmaSupport option

Chrome has an optional feature to introspect your QT theme and generate
a Chrome theme from it.  It does this by [dynamically linking QT
(if present)](https://docs.google.com/document/d/1IO6NTtnJiEVps0WlUC_lDr1bBKO72zPNTe-4msoBYXk/edit?resourcekey=0-UbCM69FptaNMGX7JXGt-3Q).

A previous PR #375279 added basic support for this (by including `qt6`
as a derivation dependency), but it was broken.  The title bar was
always cyan regardless of what theme you had chosen in KDE.

This PR adds `plasma-integration` to correctly deduce the user's chosen
theme.  It also moves the current `qt6` dependency behind the new
`plasmaSupport` flag, ensuring that users who are not utilizing the QT
theme aren't pulling in QT inadvertently.

Only `google-chrome` is in scope for this PR (because it's what I use),
but others are welcome to copy it to fulfill #228751 for Chromium
derivatives.
---
 pkgs/by-name/go/google-chrome/package.nix | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/pkgs/by-name/go/google-chrome/package.nix b/pkgs/by-name/go/google-chrome/package.nix
index 97a1d3fb0e79..419783472703 100644
--- a/pkgs/by-name/go/google-chrome/package.nix
+++ b/pkgs/by-name/go/google-chrome/package.nix
@@ -94,8 +94,10 @@
   addDriverRunpath,
   undmg,
 
-  # For QT support
+  # Enables Chrome's "Use QT" appearance to introspect the user's Plasma theme
+  plasmaSupport ? false,
   qt6,
+  kdePackages,
 
   # Create a symlink at $out/bin/google-chrome
   withSymlink ? true,
@@ -167,8 +169,12 @@ let
   ++ [
     gtk3
     gtk4
+  ]
+  ++ lib.optionals plasmaSupport [
     qt6.qtbase
     qt6.qtwayland
+    kdePackages.plasma-integration
+    kdePackages.breeze
   ];
 
   linux = stdenvNoCC.mkDerivation (finalAttrs: {
@@ -249,9 +255,13 @@ let
 
       # "--simulate-outdated-no-au" disables auto updates and browser outdated popup
       makeWrapper "$out/share/google/$appname/google-$appname" "$exe" \
-        --prefix QT_PLUGIN_PATH  : "${qt6.qtbase}/lib/qt-6/plugins" \
-        --prefix QT_PLUGIN_PATH  : "${qt6.qtwayland}/lib/qt-6/plugins" \
-        --prefix NIXPKGS_QT6_QML_IMPORT_PATH : "${qt6.qtwayland}/lib/qt-6/qml" \
+        ${lib.optionalString plasmaSupport ''
+          --prefix QT_PLUGIN_PATH  : "${qt6.qtbase}/lib/qt-6/plugins" \
+          --prefix QT_PLUGIN_PATH  : "${qt6.qtwayland}/lib/qt-6/plugins" \
+          --prefix QT_PLUGIN_PATH  : "${kdePackages.plasma-integration}/lib/qt-6/plugins" \
+          --prefix QT_PLUGIN_PATH  : "${kdePackages.breeze}/lib/qt-6/plugins" \
+          --prefix NIXPKGS_QT6_QML_IMPORT_PATH : "${qt6.qtwayland}/lib/qt-6/qml" \
+        ''} \
         --prefix LD_LIBRARY_PATH : "$rpath" \
         --prefix PATH            : "$binpath" \
         --suffix PATH            : "${lib.makeBinPath [ xdg-utils ]}" \