Ambiguity with the 1st clause of the "no scheme state" in basic parser.

[dannyniu]

What is the issue with the URL Standard?

(from https://url.spec.whatwg.org/#no-scheme-state)
The clause says:

If base is null, or base has an opaque path and c is not U+0023 (#), missing-scheme-non-relative-URL validation error, return failure.

There's an ambiguity as to whether the condition is interpreted as:

• base === null || (path_is_opaque(base) && c != "#") or
• (base === null || path_is_opaque(base)) && c != "#"

Since these 2 conditions have different outcome on some input, it is necessary this be clarified.

[dannyniu]

The description for the error code seems able to clarify it, it'd be good if some kind of note can be added.