No Gallery with Photonic Version > 2.60? Check Your CDN

If you have have upgraded to the latest version of Photonic, or any version ≥ 2.60 and you suddenly find your galleries missing, this may be happening due to a CDN issue.

CDNs are typically provided by your web hosting platforms and you might have enabled one for your site. If you have, then a change introduced in version 2.60 might be tripping up your CDN.

To verify, take a look at your JavaScript console in your browser (you can do so by keying F12, or Ctrl + Shift + I in Chrome). Do you see an error? Typically the error would look like this:

Access to script at 'https://my-host-cdn.com/path/to/photonic-lightbox.min.js?ver=xxxxxxxx-xxxxxx' from origin 'https://my-domain.com' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.

Your site’s domain is https://my-domain.com/, but your files are stored on a different server, https://my-host-cdn.com/. In version 2.60 of Photonic there was a change to modernize the JavaScript. This is loaded with a special script attribute called module. When you have a JS file loaded as a module it is subjected to CORS (Cross-Origin-Resource-Sharing) restrictions. What this means is that your script has to be on the same domain as the page where it is being invoked, or it has to be served from a different domain using a suitable ‘Access-Control-Allow-Origin’ header.

There are multiple things that can be done to resolve this, and I would recommend these two options in this order:

1. Configure your site / host to avoid pulling the Photonic JS files from the CDN. If the file is pulled from your own site, this error goes away.
2. If the above is not possible, then there is an option in Photonic itself – Photonic → Settings → Generic Options → Advanced → JavaScript Version. Pick the option that says “Include only transpiled code”. While this fixes the issue, you will not be able to take advantage of a modernized and smaller code base within Photonic.

If you are not using a CDN, then you are likely affected by a different problem. Please start a separate thread in such a case.