diff --git a/.github/workflows/container.yml b/.github/workflows/container.yml
index d785f778c..618828a98 100644
--- a/.github/workflows/container.yml
+++ b/.github/workflows/container.yml
@@ -29,10 +29,16 @@ jobs:
           username: ${{ github.actor }}
           password: ${{ github.token }}
 
+      - name: set lower case owner name
+        run: |
+          echo "OWNER_LC=${OWNER,,}" >>${GITHUB_ENV}
+        env:
+          OWNER: '${{ github.repository_owner }}'
+
       - name: Check if image already exists on GHCR
         id: check
         run: |
-          image=ghcr.io/${{ github.repository_owner }}/xdg-desktop-portal:${{ env.IMAGE_TAG }}
+          image=ghcr.io/${{ env.OWNER_LC }}/xdg-desktop-portal:${{ env.IMAGE_TAG }}
           echo "exists=$(docker manifest inspect $image >/dev/null && echo 'true' || echo 'false')" \
             >> "$GITHUB_OUTPUT"
           echo "image=$image" >> "$GITHUB_OUTPUT"
@@ -43,4 +49,4 @@ jobs:
         with:
           push: true
           file: .github/workflows/Containerfile
-          tags: ghcr.io/${{ github.repository_owner }}/xdg-desktop-portal:${{ env.IMAGE_TAG }}
\ No newline at end of file
+          tags: ghcr.io/${{ env.OWNER_LC }}/xdg-desktop-portal:${{ env.IMAGE_TAG }}
\ No newline at end of file