diff --git a/.github/workflows/build-firmware.yaml b/.github/workflows/build-firmware.yaml
index 545740b9..ade84c62 100644
--- a/.github/workflows/build-firmware.yaml
+++ b/.github/workflows/build-firmware.yaml
@@ -72,10 +72,13 @@ jobs:
 
           # Output matrix to a file
           echo matrix=$matrix >> $GITHUB_OUTPUT
+      - name: 🧪 Display generated matrix
+        run: |
+          echo "${{ steps.prepare-matrix.outputs.matrix }}"
 
   build:
     name: ${{ matrix.firmware }} / ${{ matrix.device }}
-    if: ${{ needs.prepare.outputs.matrix != '' }}
+    if: ${{ needs.prepare.outputs.matrix != '{"include":[]}' }}
     runs-on: ubuntu-latest
     needs: prepare
     strategy: