Javascript Domain Format

I am getting this error when trying to add a domain to my api key

" * The JavaScript domain address format for one or more entries is invalid. The format should consist of ‘http://’ or ‘https://’ followed by text separated by a decimal point. For example,"

My domain has the following format

I assume it doesn’t like the dashes, but that seems like a very weird restriction as there are many domains in a similar format to this one. The strange thing is I have already added a domain to this key with the exact same format awhile ago, I can’t remember how I did it but I do remember it giving me the same kind of issue back then. I just can’t figure out how I added it last time.

Can anyone help?