Bug Report
There are two duplicate keys in diagnosticMessages.json:
- "Specify the location where debugger should locate map files instead of generated locations" and
- "Emit a UTF-8 Byte Order Mark (BOM) in the beginning of output files.".
For example, vscode shows warnings like this:

🔎 Search Terms
diagnosticMessages.json
🕗 Version & Regression Information
It seems this PR #44409 added two entries which already existed.
⏯ Playground Link
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💻 Code
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🙁 Actual behavior
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🙂 Expected behavior
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