On the Contract entity there is a button called Create Invoice. When it is clicked nothing happens for about 5 seconds and then all of a sudden a new Invoice pops up. As a user this is an unsettling experience as you are not sure if anything is happening. I've seen instances where a user has created 3 copies of the same Invoice because they kept clicking the button after no immediate response. It would be good if there was a loading spinner or a pop -up message that gave the user immediate feedback while the Invoice was being generated in the background. The same button on the Contract grid view has this functionality - it would nice for it to be consistent.

On the Invoice entity there is a button called Confirm Invoice. It has a similar issue where the invoice status doesn't update for a couple of seconds and there is no feedback to the user in the meantime.