Responsive.makeResponsive() not working if /VAADIN hosted on Amazon S3

The Responsive extension is great and working like a charm for years. But I am now trying to move all static content (/VAADIN) to Amazon S3 and everything would work fine but Responsive.makeResponsive(…) isn’t working. I don’t quite understand how this responsive feature is working under the hood, would be great to get some insights on how to make this possible hosting css on S3.

Well as I have understood it the responsive extension tries to find those width-range and height-range attributes from the stylesheets through DOM. Maybe there is some cross-domain issue when trying to access. If that’s the case, then bypassing same origin policy needs to be done e.g. by using reverse proxy. Is it happening only in Firefox. This ticket explains at least some scenario
https://dev.vaadin.com/ticket/16249
The bug is closed, but from the comments it seems that there wasn’t any real fix for FF.

Thanks Johannes for your quick reply! Apparently it’s not working in Chrome either, wihtout the warning in the debug window though. My main goal was to deliver at least the big *.cache.js files from S3. Could it be solved via this technique?

https://vaadin.com/blog/-/blogs/using-cors-with-vaadin

Thanks for your help.

I have to admit I don’t know. Maybe first try to debug client-side code and verify that the problem is cross-domain issues.