Sending invitations needs a ui rsponse
When sending invitations my users send them 2 or 3 times because nothing happens when they click on the send button. Three seconds later a tiny light blue strip appears that nobody on a big screen recognises. Therefore they click the send button again and again.
The "send" button needs to give immediate feedback when it was clicked AND needs to be disabled for 5 seconds so that accidentally sending the same invitation multiple times is not possible.