diff --git a/home/linux/gui/base/desktop-tools.nix b/home/linux/gui/base/desktop-tools.nix
index 1a4e6f99..14192b02 100644
--- a/home/linux/gui/base/desktop-tools.nix
+++ b/home/linux/gui/base/desktop-tools.nix
@@ -7,6 +7,12 @@
     "MOZ_WEBRENDER" = "1";
     # enable native Wayland support for most Electron apps
     "ELECTRON_OZONE_PLATFORM_HINT" = "auto";
+    # Make Qt apps follow the GTK font and theme. Without this, Qt keeps its
+    # built-in default ("Sans Serif" 9) while GTK uses `gtk-font-name`
+    # (Noto Sans 11), so Qt apps like Telegram render visibly smaller than
+    # GTK apps. The `gtk3` platform theme plugin ships with qtbase, so no
+    # extra package is needed, and it also gets GTK file dialogs.
+    "QT_QPA_PLATFORMTHEME" = "gtk3";
     # misc
     "_JAVA_AWT_WM_NONREPARENTING" = "1";
     "QT_WAYLAND_DISABLE_WINDOWDECORATION" = "1";
diff --git a/home/linux/gui/base/gtk.nix b/home/linux/gui/base/gtk.nix
index a8415759..074b0d26 100644
--- a/home/linux/gui/base/gtk.nix
+++ b/home/linux/gui/base/gtk.nix
@@ -17,14 +17,6 @@
     size = 24;
   };
 
-  # set dpi for 4k monitor
-  xresources.properties = {
-    # dpi for Xorg's font
-    "Xft.dpi" = 150;
-    # or set a generic dpi
-    "*.dpi" = 150;
-  };
-
   # gtk's theme settings, generate files:
   #   1. ~/.gtkrc-2.0
   #   2. ~/.config/gtk-3.0/settings.ini