Lighthouse audit always return warning 'Missing source maps for large first-party JavaScript'

[danurahadi]

FAQ

• [X] Yes, my issue is not about variability or throttling.
• [X] Yes, my issue is not about a specific accessibility audit (file with axe-core instead).

URL

https://sportz.picassorewards.com:8443/login

What happened?

I face an issue of Chrome Lighthouse Audit.

I build a web app that loads Sock JS minified file.

The file is -> https://unpkg.com/sockjs-client@1.5.0/dist/sockjs.min.js

As you can see, there is //# sourceMappingURL at the end of the file.

Also, there is the source map file -> https://unpkg.com/sockjs-client@1.5.0/dist/sockjs.min.js.map

What did you expect?

I think that warning should not appear.

What have you tried?

I have tried to load the SockJS minified file from the CDN and do the Lighthouse Audit several times, but it's still produce the same warning :

Missing source maps for large first-party JavaScript

Environment :

• Ubuntu 22.04
• Brave Browser v1.50.114

Am I missing something here or there is a bug in the Lighthouse?

Thank you.

How were you running Lighthouse?

Chrome DevTools

Lighthouse Version

10.0.1

Chrome Version

112.0.5615.49

Node Version

No response

OS

Linux Ubuntu 22.04

Relevant log output

No response

[adamraine]

I don't think sockjs.min.js is causing the audit to fail, it's the other script (https://sportz.picassorewards.com:8443/_nuxt/entry.86f859b9.js) which doesn't have a source map. Are you seeing that as well?

I did also notice another error while testing your page though:

@alexnj can you investigate?

[danurahadi]

@adamraine I'm not sure about the script you mention because it's generated by Nuxt.js. And also that error message (screenshot) didn't show up on my local machine.

Maybe you Chrome guys can see the audit results from my local machine below :

Thanks so much for your response.

[adamraine]

Yeah, looks like the audit is failing because entry.c1164377.js doesn't have a source map, and not because of sockjs.min.js. This file had a different name on my.

[alexnj]

I created a follow up issue #14996 to track the chrome plugin URL breaking the audit case.

[alexnj]

Re: the original issue — it seems like the inclusion of passing source-map entries with a partially failing valid-sourcemaps audit result is the cause for confusion. We could either drop the passed entries, or rearrange them under a sub-headings as Passed / scripts with valid source maps and Failed / scripts without source maps to resolve the ambiguity in the UI. Wdyt @adamraine ?

[adamraine]

Not sure about using Passed / Failed as headings since we need the sub-headings to display the failed messages. There are definitely a few ways to approach this though:

• Passed / Failed indicators in a table column
• Put the passed / failed scripts in entirely separate tables
• Add a diagnostic message as a sub-item to passed scripts

[danurahadi]

@adamraine @alexnj thank you all guys, for the response. btw, what's the meaning of P2 label?

[adamraine]

It's the issue priority on a 1-3 scale

[danurahadi]

ah i see. thank you.