perf(legacy): skip lowering when detecting polyfills #20387
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sapphi-red
added
plugin: legacy
p2-nice-to-have
bluwy
approved these changes
Jul 16, 2025
sapphi-red
deleted the
perf/legacy-skip-lowering-when-detecting-polyfills
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Description
When detecting polyfills for modern build, plugin-legacy was lowering the code as
@babel/preset-envdoes.This PR changes that part to use
babel-plugin-polyfill-corejs3andbabel-plugin-polyfill-regenerator, which is used internally by@babel/preset-env, so that the lowering is not done.I tested this PR with https://github.com/mastodon/mastodon and it reduced the build time from 27.25s to 24.17s.