Since last week, all plugins both core and installed have stopped functioning even when enabled on our forum. Initially I thought this was something to do with the previously mentioned bug FIX: Compile missing rollup plugin bundles on demand in development - #8 but we have run multiple updates since…

I’ve got the same problem with a bunnycdn. It was working fine until a recent update. I tried adding .js to the CORS headers at bunny.net as described here: [image] Code highlighting failed because bunny.net CDN Support Someone compained that code highlightin…

Hmm. This looks like it’s an issue with your CDN: [image] [image] I enabled my CORS ignore plugin and the scripts successfully loaded but I don’t visibly see any changes from plugins. I’d recommend trying that, and if it works you should find what’s causing the error with your CDN. [ima…

Thanks Jay, we have Bunny and the fix you mentioned has sorted all the issues out now! Thank you and everyone for the help and support on this one, our forum is back to normal. Well as normal as it can be :smiley:

Glad to hear you got it sorted! [image] pfaffman: I don’t understand why this problem started when I upgraded In the new plugin system, we use script type="module", which requires the correct CORS headers to be set. Old-style script type="text/javascript" do not require those headers. We’ve…

[image] david: We’ve been slowly migrating different systems Aha. That’s what I would not have guessed.

Just a heads up for folks, if you are using Azure Classic CDN this issue has started to occur. I am trying out a fix on the CDN side, but I may need to migrate to proper front door rather than classic CDN

[image] david: In the new plugin system, we use script type="module", which requires the correct CORS headers to be set. Old-style script type="text/javascript" do not require those headers. Yep, confirmed this issue on Azure Classic CDN too. You need to add a new rule to the rules engine, e…

weirdly this issue hasn’t impacted themes, only plugins for us.

Is there somewhere to find instructions or guidance regarding these recent changes regarding CORS for those of us using Cloudflare?

@pfaffman @TomoftheFog @tanya_byrne @denvergeeks please could you confirm how your assets are configured? Do you just have a CDN + the application server? Or do you also store assets on S3/S3-compatible storage? If you are using S3/S3-compatible storage, then unfortunately the only reliable way is …

All plugins not functioning due to CORS error after recent upgrade

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TomoftheFog (Tom) March 28, 2026, 9:04am 3

Thank you so much for taking the time to look into this for us. We’ll run some tests over the weekend and update when we can.

3 Likes

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All plugins not functioning due to CORS error after recent upgrade

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