RFC 3986 (the specification for URI syntax) says that while programs should accept URI schemes of various cases, they should only output schemes in their canonical, lowercase form. In other words, if a user enters [HtTP://test.com], it should be rendered on the page as [http://test.com] (lowercase http instead of the mixed case).
Version: 1.20.x
Severity: trivial
URL: http://www.ietf.org/rfc/rfc3986.txt
Is your assertion based on the following RFC quote?
"Although schemes are case-insensitive, the canonical form is lowercase and documents that specify schemes must do so with lowercase letters."
(In reply to comment #1)
Is your assertion based on the following RFC quote?
"Although schemes are case-insensitive, the canonical form is lowercase and
documents that specify schemes must do so with lowercase letters."
Partially. It's more based on the sentence directly after that:
"An implementation should accept uppercase letters as equivalent to lowercase in scheme names (e.g., allow "HTTP" as well as "http") for the sake of robustness but should only produce lowercase scheme names for consistency."
(In reply to comment #3)
Does implementation refer to an HTML document?
Not explicitly. The RFC's intention is to treat URIs as universal, thus whether it be in an HTML document, or in an email, or written on a piece of paper, etc., it's uniform. So it's referring to any implementation of URI handling, including HTML documents.