Can someone please revisit debian-sid-ports and add tests for it? I hacked it to work locally (archive 2021 key and “buster” InRelease key), but I am not familiar enough to know what is hack and what was necessary. Proving sifive-fu540 is buildable should be enough.

Yes, sifive-fu540-sid-ports target is not currently covered by CI.
I will look into it and prepare the fix.

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