'Error: No known conditions for "./node" specifier in "msw" package' when using MSW with Vitest

src/testfile.test.ts の msw/node の import から始め、plugin を有効にした状態で Vitest 上で再現します。plugin を削除した後の結果と比較し、報告された Vite の解決エラーを追跡して、それが plugin と MSW のどちらによって引き起こされているのかを判断します。plugin が存在する状態で import が機能し、エラーが発生しなくなれば完了です。

Trying to import and use any function from MSW (specifically, msw/node) when running vitest prints this error:

 FAIL  src/testfile.test.ts [ src/testfile.test.ts ]
Error: No known conditions for "./node" specifier in "msw" package
 ❯ e node_modules/.pnpm/vite@4.5.0_@types+node@20.8.10/node_modules/vite/dist/node/chunks/dep-bb8a8339.js:21445:25
 ❯ n node_modules/.pnpm/vite@4.5.0_@types+node@20.8.10/node_modules/vite/dist/node/chunks/dep-bb8a8339.js:21445:646
 ❯ o node_modules/.pnpm/vite@4.5.0_@types+node@20.8.10/node_modules/vite/dist/node/chunks/dep-bb8a8339.js:21445:1297
 ❯ resolveExportsOrImports node_modules/.pnpm/vite@4.5.0_@types+node@20.8.10/node_modules/vite/dist/node/chunks/dep-bb8a8339.js:28746:20
 ❯ resolveDeepImport node_modules/.pnpm/vite@4.5.0_@types+node@20.8.10/node_modules/vite/dist/node/chunks/dep-bb8a8339.js:28765:31
 ❯ tryNodeResolve node_modules/.pnpm/vite@4.5.0_@types+node@20.8.10/node_modules/vite/dist/node/chunks/dep-bb8a8339.js:28453:20
 ❯ Context.resolveId node_modules/.pnpm/vite@4.5.0_@types+node@20.8.10/node_modules/vite/dist/node/chunks/dep-bb8a8339.js:28212:28
 ❯ Object.resolveId node_modules/.pnpm/vite@4.5.0_@types+node@20.8.10/node_modules/vite/dist/node/chunks/dep-bb8a8339.js:44276:32
 ❯ TransformContext.resolve node_modules/.pnpm/vite@4.5.0_@types+node@20.8.10/node_modules/vite/dist/node/chunks/dep-bb8a8339.js:43992:23

This only happens when this plugin is present, removing it seems to fix the issue.

Not sure if this is a bug in the plugin, or a problem on msw's side, or if I'm maybe doing something wrong?