diff --git a/src/FffGcodeWriter.cpp b/src/FffGcodeWriter.cpp
index dfa51260e3..cc9d350cee 100644
--- a/src/FffGcodeWriter.cpp
+++ b/src/FffGcodeWriter.cpp
@@ -2595,6 +2595,7 @@ FffGcodeWriter::InsetsPreprocessResult FffGcodeWriter::preProcessInsets(
                 }
             }
         }
+        Shape non_support_outlines_below = outlines_below;
 
         const coord_t layer_height = mesh_config.inset0_config.getLayerThickness();
 
@@ -2684,18 +2685,19 @@ FffGcodeWriter::InsetsPreprocessResult FffGcodeWriter::preProcessInsets(
         }
 
         const Shape fully_supported_region = outlines_below.offset(-half_outer_wall_width);
+        const Shape model_supported_region = non_support_outlines_below.offset(-half_outer_wall_width);
         const Shape part_print_region = part.outline.offset(-half_outer_wall_width);
 
-        const auto get_supported_region = [&fully_supported_region, &layer_height](const AngleDegrees& overhang_angle) -> Shape
+        const auto get_supported_region = [&fully_supported_region, &model_supported_region, &layer_height](const AngleDegrees& overhang_angle, bool full = true) -> Shape
         {
             // the overhang mask is set to the area of the current part's outline minus the region that is considered to be supported
-            // the supported region is made up of those areas that really are supported by either model or support on the layer below
+            // the supported region is made up of those areas that really are supported by (either) the model (or support, if 'full') on the layer below
             // expanded to take into account the overhang angle, the greater the overhang angle, the larger the supported area is
             // considered to be
             if (overhang_angle < 90.0)
             {
                 const coord_t overhang_width = layer_height * std::tan(AngleRadians(overhang_angle));
-                return fully_supported_region.offset(overhang_width + 10);
+                return (full ? fully_supported_region : model_supported_region).offset(overhang_width + 10);
             }
 
             return Shape();
@@ -2758,7 +2760,8 @@ FffGcodeWriter::InsetsPreprocessResult FffGcodeWriter::preProcessInsets(
         const AngleDegrees seam_overhang_angle = mesh.settings.get<AngleDegrees>("seam_overhang_angle");
         if (seam_overhang_angle < 90.0)
         {
-            const Shape supported_region_seam = get_supported_region(seam_overhang_angle);
+            constexpr bool not_full = false; // Do not take support into account for the seam overhang.
+            const Shape supported_region_seam = get_supported_region(seam_overhang_angle, not_full);
             gcode_layer.setSeamOverhangMask(part_print_region.difference(supported_region_seam).offset(10));
         }
         else