Right now it is not possible to have URIs without a scheme for relative links. Unfortunately normalize_scheme makes sure that there is always a // in place.
The documentation itself gives the example of <a href="//admin/dashboard/">Admin dashboard</a>. If admin is not a hostname/domain, this would not lead anywhere. I would suggest that admin/dashboard/ would be the better URI to build here.
I would suggest to change normalize_scheme to accept an empty string as well.
Right now it is not possible to have URIs without a scheme for relative links. Unfortunately
normalize_schememakes sure that there is always a//in place.The documentation itself gives the example of
<a href="//admin/dashboard/">Admin dashboard</a>. Ifadminis not a hostname/domain, this would not lead anywhere. I would suggest thatadmin/dashboard/would be the better URI to build here.I would suggest to change
normalize_schemeto accept an empty string as well.