external links check ignores blanks
If you add something like [[http: //google.com]] our external link checker fails.
it makes from that a meta entry of "externallinks": [ "http:%20//google.com"
If you click on the link you can create an item with the "name": " //google.com",
which is also not correct. But also it is not wanted to have a name like "http: //google.com"