Marc Hassan

I don't think this deals with all deprecations; when I use the `emit` phase, I get this: ```txt (node:80564) [DEP_WEBPACK_COMPILATION_ASSETS] DeprecationWarning: Compilation.assets will be frozen in future, all modifications are...

This alternative did the trick for me: https://www.npmjs.com/package/google-closure-library-webpack-plugin

It looks like BrowserStack does not have Safari 12.0 (it only has 12.1), so it would be difficult to validate the fix.

If I fire up `iPhone 8` in BrowserStack and load that URL, I see `ios_saf/12.0.0`, but if I load up the [test page](https://abelyao.github.io/others/ios12-safari-bug.html), the issue doesn't seem to replicate. I'm...

`structuredClone` is not 100% polyfill-able, but the `core-js` implementation seems to get pretty close, with only a few [caveats](https://github.com/zloirock/core-js#caveats-when-using-structuredclone-polyfill). @JakeChampion What do you think?

Besides `devicePixelRatio`, is there a list of the polyfills that should get an alias?

As far as I can tell, an `HTMLFormElement.prototype.reportValidity` polyfill would need to depend on `HTMLFormElement.prototype.checkValidity`, which is only available in IE10+ ([link](https://caniuse.com/mdn-api_htmlformelement_checkvalidity)) and may not be polyfillable. Some reference implementations...

Related: https://github.com/Financial-Times/polyfill-library/issues/203

Can you provide a reproduction? I don't quite follow the use case.

i think it would be helpful to have individual issues for each of these defective polyfills, with the appropriate level of detail. i would be happy to help pick up...