[jakelazaroff]

It’s still a tradeoff, though. Let’s say a website has three pages: /a, /b and /c. Two of those pages, /a and /b, each use the module `foo`. Where should `foo` get bundled? If you put it in the “common” bundle, it’ll get served to /c even though it’s not needed. If you put it in both of the bundles for /a and /b, the client will download it twice.

[eyelidlessness]

Most bundlers:

- have more sophisticated dependency tracking and will split a separate chunk for a/b

- can produce some kind of a manifest to allow you to preload and avoid nested waterfalls

- provide some mechanism for greater control over what gets chunked separately or combined, for the usage/caching scenarios you’ll undoubtedly know better than a general purpose program

[wruza]

You don’t have to have a single bundle or just main one and common one. Split into as many as you (or a bundler) see fit. In the worst degenerate case you’ll end up with every module bundled separately and preloaded on every page, just like ESM, but without deferred roundtrips for nested dependencies.