The parameter's value as one URL path segment: its text URI-encoded, or
"null" when the value is nullish.
. and .. are refused. encodeURIComponent leaves them as they are, and
the URL parser that fetch and new URL() share resolves them as dot
segments, so the request would reach the parent path instead of the route,
with the value gone. Their percent-encoded form is a dot segment by the
same standard, so no spelling carries them.
The parameter's value as one URL path segment: its text URI-encoded, or
"null"when the value is nullish..and..are refused.encodeURIComponentleaves them as they are, and the URL parser thatfetchandnew URL()share resolves them as dot segments, so the request would reach the parent path instead of the route, with the value gone. Their percent-encoded form is a dot segment by the same standard, so no spelling carries them.