diff --git a/internal/resource/http.go b/internal/resource/http.go
index 1cc621fc09..eafe17319d 100644
--- a/internal/resource/http.go
+++ b/internal/resource/http.go
@@ -212,6 +212,8 @@ func (f *Fetcher) RewriteCAsWithDataUrls(cas []types.Resource) error {
 
 		encoded := dataurl.EncodeBytes(blob)
 		cas[i].Source = &encoded
+		// the rewrite wipes the compression
+		cas[i].Compression = nil
 	}
 	return nil
 }