But hmm, now I removed all my port forwards and tried again, and it worked. A bit counterintuitive though that you select a host, then go back and see it selected, then click close. But it works so I don't mind.

I noticed another bug though:

The port forwards are supposed to allow multiple ports, separated by '-'. So something like '22-80-443' would probably be common. But the external ports don't pass validation if I enter more than two ports. Internal passed once I edit the external field. So something is definitely wrong there.

I've always defined every port separately, but it would be pretty convenient if I could put all the ports for one host in one definition.

  @McFox 

Hi, thanks for your feedback here.

If you set like "22-80" for both Internal and External Port, did you test both ports can be opened and the function works properly?

As I know, Only one port can be open at a time. You may refer to the guide.