Redundant require('@vue/devtools-api') in the CJS prod build

[haoqunjiang]

Version

4.1.3

Reproduction link

unpkg.com

Steps to reproduce

Cmd + F, search for require('@vue/devtools-api') on the page

What is expected?

The require statement should be tree-shaken away from the bundle, because non of its exports are used in the prod bundle of vue-router, and the package is of sideEffects: false:
https://github.com/vuejs/devtools/blob/ba54bb770a829429226a630dd5dbedcf596f27ef/packages/api/package.json#L9

What is actually happening?

It remains in the CJS prod bundle

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Originally reported at vuejs/devtools-v6#1932
As my comment on the issue, it's not a big issue as most users would use the esm-bundler version, which could be correctly tree-shaken.
But this issue still indicates that something might be wrong in vue-router's rollup config.

[posva]

It's funny, we were just talking about this with the Nuxt team yesterday for pinia: vuejs/pinia#1561

It does seem like a bug in rollup (or maybe intentional for perf reasons) but we did find a way to remove it so I will just apply the same change