[release/9.0] [browser][host] Apply CORS also to .mjs files was closed without merge

[boppbo]

Description

PR #108680 was closed without merge.

Running multi-threaded wasm standalone is not possible. Any pointers how i can build the package myself as a workaround?

Reproduction Steps

See #108680

Expected behavior

See #108680

Actual behavior

See #108680

Regression?

No response

Known Workarounds

No response

Configuration

No response

Other information

No response

[dotnet-policy-service]

Tagging subscribers to 'arch-wasm': @lewing
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[pavelsavara]

Multi-threading is experimental feature in Net9, please switch to Net10 previews.