diff --git a/Dockerfile b/Dockerfile
index a5f45fc..eff2c2c 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -20,6 +20,9 @@ RUN pip install --upgrade pip && \
     pip install --upgrade setuptools && \
     pip install matrix-synapse==v${VERSION} psycopg2-binary python-ldap matrix-synapse-ldap3 lxml publicsuffix2 git+https://github.com/matrix-org/synapse-s3-storage-provider.git@${STORAGE_PROVIDER_VERSION} matrix-synapse[oidc]
 
+# workaround (https://github.com/matrix-org/synapse/issues/15873) . remove after 1.87.0
+RUN sed -e "s/Image.ANTIALIAS/Image.LANCZOS/" -i /app/code/env/lib/python3.10/site-packages/synapse/media/thumbnailer.py
+
 RUN ln -sf /app/data/index.html /app/code/env/lib/python3.10/site-packages/synapse/static/index.html
 
 RUN chown -R cloudron.cloudron /app/code