diff --git a/home/hosts/linux/idols-kana.nix b/home/hosts/linux/idols-kana.nix
index e1bd015b..d8e318e8 100644
--- a/home/hosts/linux/idols-kana.nix
+++ b/home/hosts/linux/idols-kana.nix
@@ -7,4 +7,6 @@
   modules.desktop.computerUse.enable = true;
   # localhost-only VNC server for manual access (use an SSH tunnel).
   modules.desktop.computerUse.vnc = true;
+  # trycua/cua driver.
+  modules.desktop.computerUse.cuaDriver = true;
 }
diff --git a/home/hosts/linux/idols-ruby.nix b/home/hosts/linux/idols-ruby.nix
index caed30d1..d8e318e8 100644
--- a/home/hosts/linux/idols-ruby.nix
+++ b/home/hosts/linux/idols-ruby.nix
@@ -7,6 +7,6 @@
   modules.desktop.computerUse.enable = true;
   # localhost-only VNC server for manual access (use an SSH tunnel).
   modules.desktop.computerUse.vnc = true;
-  # trycua/cua driver, grey-tested on ruby only.
+  # trycua/cua driver.
   modules.desktop.computerUse.cuaDriver = true;
 }
diff --git a/home/linux/gui/i3/default.nix b/home/linux/gui/i3/default.nix
index b0fea7ed..3b3c0acc 100644
--- a/home/linux/gui/i3/default.nix
+++ b/home/linux/gui/i3/default.nix
@@ -54,11 +54,6 @@ let
       DBUS_SESSION_BUS_ADDRESS="unix:path=''${XDG_RUNTIME_DIR}/bus" \
       ${pkgs.glib.bin}/bin/gsettings set org.gnome.desktop.interface toolkit-accessibility true \
       >/dev/null 2>&1 || true
-
-    ${lib.optionalString cfg.cuaDriver ''
-      # cua-driver sends content-free telemetry by default; turn it off.
-      ${pkgs.cua-driver}/bin/cua-driver telemetry disable >/dev/null 2>&1 || true
-    ''}
   '';
 in
 {
@@ -201,6 +196,9 @@ in
           "DISPLAY=${display}"
           "XDG_SESSION_TYPE=x11"
         ];
+        # cua-driver sends content-free telemetry by default. Do this before
+        # the daemon starts so activation does not depend on the i3 session.
+        ExecStartPre = "${pkgs.cua-driver}/bin/cua-driver telemetry disable";
         ExecStart = "${pkgs.cua-driver}/bin/cua-driver serve";
         Restart = "always";
         RestartSec = 2;
diff --git a/hosts/README.md b/hosts/README.md
index c05b9a75..677546b0 100644
--- a/hosts/README.md
+++ b/hosts/README.md
@@ -30,11 +30,11 @@ directory.
 
 The `agent` hosts differ only in:
 
-|              | `aquamarine`                               | `ruby`              | `kana`        |
-| ------------ | ------------------------------------------ | ------------------- | ------------- |
-| Computer use | off                                        | on, with cua-driver | on            |
-| Hardware     | physical; 2x R9700, NPU speech recognition | libvirt guest       | libvirt guest |
-| Root         | tmpfs; `preservation.nix` keeps home state | disk                | disk          |
+|              | `aquamarine`                               | `ruby`              | `kana`              |
+| ------------ | ------------------------------------------ | ------------------- | ------------------- |
+| Computer use | off                                        | on, with cua-driver | on, with cua-driver |
+| Hardware     | physical; 2x R9700, NPU speech recognition | libvirt guest       | libvirt guest       |
+| Root         | tmpfs; `preservation.nix` keeps home state | disk                | disk                |
 
 `outputs/x86_64-linux/tests/agent-profile` checks the `agent` rows.
 
diff --git a/hosts/idols-ruby/default.nix b/hosts/idols-ruby/default.nix
index 6586e652..0a576e5e 100644
--- a/hosts/idols-ruby/default.nix
+++ b/hosts/idols-ruby/default.nix
@@ -19,15 +19,6 @@ in
   # Headless computer-use environment (Xvfb + i3 + desktop automation + browser).
   modules.desktop.computerUse.enable = true;
 
-  # Enable binfmt emulation of aarch64-linux, this is required for cross compilation.
-  boot.binfmt.emulatedSystems = [
-    "aarch64-linux"
-    "riscv64-linux"
-  ];
-  # This enables the kernel to preload the emulator binaries when the binfmt registrations are added,
-  # obviating the need to make the emulator binaries available inside chroots and chroot-like sandboxes.
-  boot.binfmt.preferStaticEmulators = true; # required to work with podman
-
   # supported file systems, so we can mount any removable disks with these filesystems
   boot.supportedFilesystems = [
     "ext4"
diff --git a/outputs/x86_64-linux/tests/computer-use-headless/expected.nix b/outputs/x86_64-linux/tests/computer-use-headless/expected.nix
index 671bfdac..cd6530dc 100644
--- a/outputs/x86_64-linux/tests/computer-use-headless/expected.nix
+++ b/outputs/x86_64-linux/tests/computer-use-headless/expected.nix
@@ -17,7 +17,8 @@ lib.genAttrs hosts (name: {
   i3Restart = "always";
   vnc = true;
   clipboardSync = true;
-  cuaDriver = name == "ruby";
+  cuaDriver = true;
+  cuaTelemetryDisabled = true;
   brave = true;
   chromium = true;
 })
diff --git a/outputs/x86_64-linux/tests/computer-use-headless/expr.nix b/outputs/x86_64-linux/tests/computer-use-headless/expr.nix
index 8195c094..b69c47ba 100644
--- a/outputs/x86_64-linux/tests/computer-use-headless/expr.nix
+++ b/outputs/x86_64-linux/tests/computer-use-headless/expr.nix
@@ -29,6 +29,9 @@ lib.genAttrs hosts (
       "autocutsel-clipboard"
     ];
     cuaDriver = home.modules.desktop.computerUse.cuaDriver;
+    cuaTelemetryDisabled = lib.hasInfix "telemetry disable" (
+      home.systemd.user.services.cua-driver.Service.ExecStartPre
+    );
     brave = home.programs.brave-origin.enable;
     chromium = home.programs.chromium.enable;
   }