openrtb.version.unsupported
What it means
You asked for validation against a version RTBlint has no usable catalog for. The one live example is 2.6-202204, whose source document does not yield a machine-readable catalog. Rather than run a hollow check and report the payload clean, validation refuses.
Why it matters
A validator that silently passes everything is worse than none: it launders broken payloads into a green checkmark. The explicit refusal tells you the coverage gap exists so you can validate against an adjacent snapshot instead.
How to fix it
Validate against the nearest supported snapshot (for 2.6-202204, use 2.6-202210). The versions page lists every tracked snapshot and its catalog status.
Check your payload
Paste a bid request or response into the tester to see whether this code fires against it, or gate on the id in CI with the CLI: the id is stable, wording is not.
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