diff --git a/CHANGES b/CHANGES
index 3a7b590f8..0db36e95a 100644
--- a/CHANGES
+++ b/CHANGES
@@ -20,6 +20,7 @@ Emulation fixes:
  - GB Memory: Initialize HRAM when skipping BIOS in GBC mode (fixes mgba.io/i/3420)
  - GB Serialize: Add missing Pocket Cam state to savestates
  - GB Video: Implement DMG-style sprite ordering
+ - GB Video: Fix window enable edge case (fixes mgba.io/i/2640)
  - GBA: Unhandled bkpt should be treated as an undefined exception
  - GBA: Add baseline CP0 (Wii U VC) and CP1 (DCC) implementations
  - GBA Serialize: Fix some minor save state edge cases
diff --git a/cinema/gb/window/smurfs-score/baseline_0000.png b/cinema/gb/window/smurfs-score/baseline_0000.png
new file mode 100644
index 000000000..28e647945
Binary files /dev/null and b/cinema/gb/window/smurfs-score/baseline_0000.png differ
diff --git a/cinema/gb/window/smurfs-score/baseline_0001.png b/cinema/gb/window/smurfs-score/baseline_0001.png
new file mode 100644
index 000000000..4f65732ea
Binary files /dev/null and b/cinema/gb/window/smurfs-score/baseline_0001.png differ
diff --git a/cinema/gb/window/smurfs-score/baseline_0002.png b/cinema/gb/window/smurfs-score/baseline_0002.png
new file mode 100644
index 000000000..4d39f3c21
Binary files /dev/null and b/cinema/gb/window/smurfs-score/baseline_0002.png differ
diff --git a/cinema/gb/window/smurfs-score/baseline_0003.png b/cinema/gb/window/smurfs-score/baseline_0003.png
new file mode 100644
index 000000000..a746b2efd
Binary files /dev/null and b/cinema/gb/window/smurfs-score/baseline_0003.png differ
diff --git a/cinema/gb/window/smurfs-score/test.mvl b/cinema/gb/window/smurfs-score/test.mvl
new file mode 100644
index 000000000..7e30d877e
Binary files /dev/null and b/cinema/gb/window/smurfs-score/test.mvl differ
diff --git a/src/gb/renderers/software.c b/src/gb/renderers/software.c
index 76a0c55da..08e703b19 100644
--- a/src/gb/renderers/software.c
+++ b/src/gb/renderers/software.c
@@ -268,7 +268,7 @@ static void GBVideoSoftwareRendererUpdateWindow(struct GBVideoSoftwareRenderer*
 	if (renderer->lastY >= GB_VIDEO_VERTICAL_PIXELS || !(after || before)) {
 		return;
 	}
-	if (!renderer->hasWindow && renderer->lastX == GB_VIDEO_HORIZONTAL_PIXELS) {
+	if (!renderer->hasWindow && renderer->lastX == GB_VIDEO_HORIZONTAL_PIXELS && renderer->lastY != oldWy) {
 		return;
 	}
 	if (renderer->lastY >= oldWy) {