diff --git a/src/main.cpp b/src/main.cpp
index 23596eb..9b7af44 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -2359,8 +2359,12 @@ int main(int argc, char* argv[])
             const bool backdropNeedsFrames = (backdrop_active || app.getGradientTexture() != 0)
                                           && !opaqueBackground;
             const bool reduceMotion = app.settings() && app.settings()->getReduceMotion();
+            // C128: suppress backdrop theme-effect frame requests while a blur overlay (a modal dialog or
+            // the lock screen) covers them -- they aren't visible, and the overlay's own moving elements
+            // request frames via RequestProgressFrame(), so this never freezes anything on screen.
             const bool effectsAnimating = !reduceMotion
-                && dragonx::ui::effects::ThemeEffects::instance().hasActiveAnimation();
+                && dragonx::ui::effects::ThemeEffects::instance().hasActiveAnimation()
+                && !dragonx::ui::material::AnyBlurOverlayActiveLastFrame();
             const bool ambient = effectsAnimating
                               || backdropNeedsFrames
                               || avatarAnimating