The website does not clearly identify RFCs that have Historic status. An RFC can be published with its status set to Historic (e.g., https://www.rfc-editor.org/info/rfc5773/ -- see the header Category: Historic) or they can be moved to Historic (e.g., https://www.rfc-editor.org/info/rfc6379/ per this announcement: https://mailarchive.ietf.org/arch/msg/ietf-announce/0DUsq7LlywixB9c0I8KqXGggbTg/).
For these two examples, Purple has the correct status set.
The website does not clearly identify RFCs that have Historic status. An RFC can be published with its status set to Historic (e.g., https://www.rfc-editor.org/info/rfc5773/ -- see the header
Category: Historic) or they can be moved to Historic (e.g., https://www.rfc-editor.org/info/rfc6379/ per this announcement: https://mailarchive.ietf.org/arch/msg/ietf-announce/0DUsq7LlywixB9c0I8KqXGggbTg/).For these two examples, Purple has the correct status set.