diff --git a/install/config/theme.sh b/install/config/theme.sh
index 439ec08d..0dab91ad 100644
--- a/install/config/theme.sh
+++ b/install/config/theme.sh
@@ -24,4 +24,4 @@ sudo mkdir -p /etc/brave/policies/managed
 sudo chmod a+rw /etc/brave/policies/managed
 
 # Default Chromium to follow system appearance ("device") instead of dark
-echo '{"browser":{"theme":{"color_scheme":0}}}' | sudo tee /usr/lib/chromium/initial_preferences >/dev/null
+echo '{"browser":{"theme":{"color_scheme":0,"color_scheme2":0}}}' | sudo tee /usr/lib/chromium/initial_preferences >/dev/null
diff --git a/migrations/1777018408.sh b/migrations/1777018408.sh
new file mode 100644
index 00000000..af644b53
--- /dev/null
+++ b/migrations/1777018408.sh
@@ -0,0 +1,9 @@
+echo "Fix Chromium appearance mode to also set color_scheme2 (the field Chromium actually reads now)"
+
+echo '{"browser":{"theme":{"color_scheme":0,"color_scheme2":0}}}' | sudo tee /usr/lib/chromium/initial_preferences >/dev/null
+
+# Update existing Chromium profiles so color_scheme2 follows the system, not dark
+PREFS="$HOME/.config/chromium/Default/Preferences"
+if [[ -f "$PREFS" ]] && command -v jq &>/dev/null; then
+  jq '.browser.theme.color_scheme = 0 | .browser.theme.color_scheme2 = 0' "$PREFS" > "$PREFS.tmp" && mv "$PREFS.tmp" "$PREFS"
+fi