Adding link action fails with no UI feedback

My client recently tried to add a link which had an unrecognised top level domain. Once I realised this was the issue, adding the tld fixed their issue but I just wanted to point out that the action gave the user no feedback as to what was wrong or that anything was wrong at all. The squirly circle kept going round, making it seem like sopmething was happening but nothing happened.

I think this could be improved?