There are a lot of questions on SO regarding scheme relative URL, but I don't understand what will happen in these scenarios:
1) I am on HTTPS clicking on
href="//example.com/" (example.com doesn't have SSL (it's HTTP), so browser will try to open
HTTPS://example.com/ (because it wants to match the current scheme) and if there won't be HTTPS scheme it will open
2) Vice-versa going from HTTP to HTTPS, when the target
//example.com/ is only HTTPS. Will browser open HTTPS if the destination target does not have HTTP?