System Integrity Protection prevents the required plugin from being installed. Few minutes ago I’ve got a comment: “I can’t paste the file “libstdc++.6.0.9″ , says that I don’t have the permission”. This happens when you have system file protection ENABLED.
If system file protection (SIP, System Integrity Protection) is enabled, you will not be able to upload a your file to lib. In this case you need to TURN IT OFF. You can turn it back on if you REALLY want to.

System Integrity Protection
- Restart the computer in recovery mode by holding CMD + R…
- From the Utilities menu, select Terminal…
- In the terminal, run the command “- csrutil disable” (for BIG SUR and Monterey needs 2 commands: csrutil disable and csrutil authenticated-root disable)
- Reboot…
Now Your are able to upload a your file to lib.
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