Random errors using dev server in Firefox: "Loading failed for the module" & NS_ERROR_NET_PARTIAL_TRANSFER

[jordanade]

Running VITE v5.4.7 and LARAVEL v10.48.22 (plugin v1.0.5). Running "npm run dev". Using Firefox 130 on Mac. Using about 40 inputs.

Page loads only work roughly half the time. Very often one or more modules will fail to load. Seems to happen more on initial page load but not always. After reloading several times, each with different module loading failures, I am eventually able to get it to work.

Console shows "Loading failed for the module with source ___". Network inspector shows modules failed with NS_ERROR_NET_PARTIAL_TRANSFER error.

Works fine on Chrome.

Anyone have any intuition about what would be causing this? I've already verified that it also happens in Firefox Safe Mode with no extensions.

[jake-low]

You mentioned that you tried in Firefox Safe Mode and the issue persisted, but in my case I was experiencing very similar symptoms and eventually found that uBlock Origin was blocking a dependency of my project from loading. I would have expected this to be fine, and that other chunks of the bundle would still load, but instead it seemed to prevent the entire app from starting. I suspect this has something to do with how Vite's dev server works, because it doesn't happen when my app is deployed in production. Disabling uBlock Origin on the page resolved the issue for me.

Posting this just in case it helps you track down your own issue - maybe Firefox's built-in tracking protection is blocking a script and causing the issue in your case? (not sure if that still runs in Safe Mode)

[linus-jansson]

I think this is not really related to vite but to how firefox handles ES modules.. My lib built with esbuild is not loading half the time on the project im working on. Disabling ublock did nothing on my end and safemode (base firefox) does not do anything. However, moving over to chrome resolves any fetch errors.

Im going to try to push my code to a "production" env to test the same out. Maybe just a localhost thing..

[luketanner]

I think this is not really related to vite but to how firefox handles ES modules

I suspect this isn't correct (or at least, not the full picture) -- I've been encountering these errors too, but notably it also happens intermittently for compiled/bundled .css files, not just .js files.

(For context: running Vite 5.4.6 with Angular 18)

[linus-jansson]

Interesting finding, only encountered it on Firefox on localhost around 40-60% of the time when I was refreshing. No issues fetching css though.

Going to production seems to be no problem at all, and all testing outside of the Gecko driver the issue just doesn't seem to exist at all!

Most odd..