Legacy build seems not work, still have optional chain

[Spike-Leung]

From https://github.com/mozilla/pdfjs-dist :

For usage with older browsers or environments, without support for modern features such as optional chaining, nullish coalescing, and private class fields/methods; please see the legacy/ folder.

After npm install pdfjs-dist and import pdfjs-dist/legacy/build/pdf.js, it still has modern features.

I also searched on the GitHub repo, it seems there are no modern features in the legacy build:

According to the README, these features should not be included in the legacy build.

Is there something wrong with my operation?

Configuration:

• PDF.js version: 3.6.172
• Is a browser extension: no

Steps to reproduce the problem:

1. npm install pdfjs-dist
2. open node_module/pdfjs-dist/legacy/build/pdf.js and check the code

[Snuffleupagus]

From https://github.com/mozilla/pdfjs-dist :

Unfortunately, because of various issues, that GitHub repository no longer updates correctly and it's consequently outdated.

If you instead look at https://www.npmjs.com/package/pdfjs-dist you'll notice slightly updated compatibility text, with a link to https://github.com/mozilla/pdf.js/wiki/Frequently-Asked-Questions#faq-support that always contains the current support data.

If you compare our list of supported browsers/environments you'll notice that all of them have native support for optional chaining, please see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Optional_chaining#browser_compatibility

PDF.js version: 3.6.172

That version is no longer supported, please find the latest releases at https://mozilla.github.io/pdf.js/getting_started/#download

[Spike-Leung]

Thanks :)