diff --git a/fiv-master.nix b/fiv-master.nix
index 37ab682..7c549a2 100644
--- a/fiv-master.nix
+++ b/fiv-master.nix
@@ -20,6 +20,7 @@ pkgs.stdenv.mkDerivation rec {
 	];
 
 	buildInputs = with pkgs; [
+		gnome.adwaita-icon-theme
 		gtk3
 		libwebp
 		libraw
@@ -74,8 +75,11 @@ pkgs.stdenv.mkDerivation rec {
 		"-Dresvg=enabled"
 	];
 
+	# See nixpkgs commit b1e73fa2e086f1033a33d93524ae2a1781d12b95 about icons.
+	# It used to work automatically.
 	preFixup = ''
 		gappsWrapperArgs+=(
+			--prefix XDG_DATA_DIRS : "$XDG_ICON_DIRS"
 			--prefix PATH : $out/bin:${pkgs.lib.makeBinPath [ pkgs.exiftool ]}
 		)
 	'';
diff --git a/logdiag-master.nix b/logdiag-master.nix
index 82bf3d2..6f06748 100644
--- a/logdiag-master.nix
+++ b/logdiag-master.nix
@@ -13,6 +13,7 @@ pkgs.stdenv.mkDerivation rec {
 	];
 
 	buildInputs = with pkgs; [
+		gnome.adwaita-icon-theme
 		gtk3
 		json-glib
 		lua5_2
@@ -53,6 +54,14 @@ pkgs.stdenv.mkDerivation rec {
 		"-DBUILD_TESTING=ON"
 	];
 
+	# See nixpkgs commit b1e73fa2e086f1033a33d93524ae2a1781d12b95 about icons.
+	# It used to work automatically.
+	preFixup = ''
+		gappsWrapperArgs+=(
+			--prefix XDG_DATA_DIRS : "$XDG_ICON_DIRS"
+		)
+	'';
+
 	doCheck = true;
 
 	checkPhase = with pkgs; ''