I have a PDF viewer widget in my FlutterFlow app. When I use a dynamically changed string for the PDF path from a Firebase collection, it doesn't work and doesn't show me my file, but if I use a manually copied path string from Firebase collection from the same file , everything works fine. Why? Thanks for helps. It occurs because a issue "Access to XMLHttpRequest at xxxxx .been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on "