pt-spec.txt describes using `keyid=fingerprint` in torrc `Bridge` lines
dcf pointed out in this comment on #10559 (moved) that pt-spec.txt claims that little-t tor's parsing of Bridge lines was extended to support keyid=fingerprint (where fingerprint is the digest of the bridge's ID key).
Little-t tor does not support this keyid= prefix. I've tested it; see comment 3 and comment 4 on #9449 (moved). Since it wasn't ever implemented, the keyid= prefix to bridge fingerprints should be removed from pt-spec.txt L27.
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