diff --git a/src/renderer/Metal.zig b/src/renderer/Metal.zig
index b9f9cc93c..f50de2f6a 100644
--- a/src/renderer/Metal.zig
+++ b/src/renderer/Metal.zig
@@ -2118,6 +2118,8 @@ fn rebuildCells(
     //     std.log.warn("[rebuildCells time] {}\t{}", .{start_micro, end.since(start) / std.time.ns_per_us});
     // }
 
+    _ = screen_type; // we might use this again later so not deleting it yet
+
     // Create an arena for all our temporary allocations while rebuilding
     var arena = ArenaAllocator.init(self.alloc);
     defer arena.deinit();
@@ -2154,12 +2156,9 @@ fn rebuildCells(
         switch (self.config.padding_color) {
             .background => {},
 
-            .extend => {
-                self.uniforms.padding_extend.up = screen_type == .alternate;
-                self.uniforms.padding_extend.down = screen_type == .alternate;
-            },
-
-            .@"extend-always" => {
+            // For extension, assume we are extending in all directions.
+            // For "extend" this may be disabled due to heuristics below.
+            .extend, .@"extend-always" => {
                 self.uniforms.padding_extend = .{
                     .up = true,
                     .down = true,
@@ -2209,9 +2208,9 @@ fn rebuildCells(
             .background, .@"extend-always" => {},
 
             // Apply heuristics for padding extension.
-            .extend => if (y == 0 and screen_type == .primary) {
+            .extend => if (y == 0) {
                 self.uniforms.padding_extend.up = !row.neverExtendBg();
-            } else if (y == self.cells.size.rows - 1 and screen_type == .primary) {
+            } else if (y == self.cells.size.rows - 1) {
                 self.uniforms.padding_extend.down = !row.neverExtendBg();
             },
         }
diff --git a/src/renderer/OpenGL.zig b/src/renderer/OpenGL.zig
index e35850874..2b6ed82a8 100644
--- a/src/renderer/OpenGL.zig
+++ b/src/renderer/OpenGL.zig
@@ -1172,6 +1172,8 @@ pub fn rebuildCells(
     cursor_style_: ?renderer.CursorStyle,
     color_palette: *const terminal.color.Palette,
 ) !void {
+    _ = screen_type;
+
     // Bg cells at most will need space for the visible screen size
     self.cells_bg.clearRetainingCapacity();
     self.cells.clearRetainingCapacity();
@@ -1216,12 +1218,7 @@ pub fn rebuildCells(
         switch (self.config.padding_color) {
             .background => {},
 
-            .extend => {
-                self.padding_extend_top = screen_type == .alternate;
-                self.padding_extend_bottom = screen_type == .alternate;
-            },
-
-            .@"extend-always" => {
+            .extend, .@"extend-always" => {
                 self.padding_extend_top = true;
                 self.padding_extend_bottom = true;
             },
@@ -1283,9 +1280,9 @@ pub fn rebuildCells(
             .background, .@"extend-always" => {},
 
             // Apply heuristics for padding extension.
-            .extend => if (y == 0 and screen_type == .primary) {
+            .extend => if (y == 0) {
                 self.padding_extend_top = !row.neverExtendBg();
-            } else if (y == self.grid_size.rows - 1 and screen_type == .primary) {
+            } else if (y == self.grid_size.rows - 1) {
                 self.padding_extend_bottom = !row.neverExtendBg();
             },
         }